Pest Management

Overview: Integrated Pest Management

Integrated Pest Management (IPM) is the coordinated use of pest and environmental information to design and implement pest control methods that are economically, environmentally and socially sound. IPM promotes prevention over remediation and integrates multiple control strategies to achieve long-term pest management solutions.

IPM is a decision-making strategy based in scheduled, systematic observation and documentation of crop health and environmental conditions. Preventative measures are built into the production system in anticipation of potential issues. Actions are taken in response to established thresholds, and results are documented.

  • Accurate pest identification is important; misidentification of pests is a common cause of pest control failure and crop damage. See the Diagnostics for Plant Problems (page 66) and Northeast Vegetable & Strawberry Pest Identification Guide for help. There are also many excellent on-line resources.
  • Biology and life-cycle of  pests reveal vulnerable stages for successful control measures. Detailed, pest-specific information is available in fact sheets on IPM web sites or publications listed in the References and Resources section. See also specific pest listings in this Guide.
  • Scouting is systematic, regular inspection of crops to quantify pest populations or crop injury. Scouting techniques vary depending upon the type of pests (weed, insect, disease or other) involved. Details are available in pest and crop-specific IPM fact sheets and manuals, and in pest listings in this Guide.
  • Monitoring weather trends and trap catches can be used to assess or predict current or future pest problems and help to prevent crop damage. Equipment and procedures vary by pest (for details see references mentioned above). Disease forecasting and insect development models for local conditions in many states can also be accessed at www.NEWA.cornell.edu.
  • Action thresholds. When systematic scouting documents pest numbers in excess of research-based thresholds, active control measures are recommended to prevent or minimize economic loss.  Such results may be expressed, for example, as 7 moths/week, 2 weeds/foot of row, or 20% defoliation, or as a rating for weather conditions like "15 Disease Severity Units.”  Some thresholds are given for pests in the individual crop sections in this manual and others vary by state or region. Contact your state's Extension IPM personnel for local action thresholds.
  • Regular record-keeping. Good records help determine which pest control strategies are working and where improvements should be made in the future. Try to keep track of scouting results, crop conditions and control procedures all season.

Preventative and curative control methods are built into an IPM management plan for each pest, crop and farm. Pesticides are used when additional control measures beyond the following methods are required.

  • Cultural controls are modifications of the crop production systems that create unsuitable conditions for pests. Examples include: appropriate site selection; crop rotation modification of planting times or spacing; precision water and nutrient management for better crop health; weed control to improve air circulation; subsoiling to improve drainage; sanitization of machinery between fields; and the use of cover and smother crops.
  • Mechanical and physical controls consist of using supplies, equipment, or some factor, such as temperature, humidity or light, to disrupt pest life cycles and/or suppress populations. Mechanical and physical controls function by cutting, crushing, burying or excluding pests with implements and barriers, or by heating, cooling, drying, wetting, or regulating light in some way. Some examples include: the use of hot-water-treated seed; plowing to bury infected crop residue; cultivation or flaming for weed control; plastic or organic mulches for weed suppression; row covers to accelerate crop growth and exclude pests; greenhouse ventilation; washing; cold storage; and roguing infected plants.
  • Breeding for resistance is a process of selecting for crop varieties that are resistant or tolerant to pathogenic microorganisms. There has also been breeding for insect and nematode resistance. Some breeding has been done to favor growth characteristics that enable plants to withstand disease pressure (such as rapid emergence, heat or cold tolerance, canopy or leaf traits). Recombinant DNA technology (“genetic modification”) has been used in a few vegetable crops to achieve resistance by incorporating traits from non-related organisms; examples are virus resistance in summer squash and caterpillar resistance in sweet corn (through expression of the Bt protein toxin in plant tissues). At this time, these are the only genetically modified vegetables available for market production.
  • Biological control is the use of naturally occurring or introduced beneficial organisms to control or suppress pest populations. Biological control agents come in all shapes and forms including: insects, mites, spiders, nematodes, fungi, bacteria, viruses, protozoa and plants. In the broadest interpretation, they would include things like microbial pesticides and the use of trap crops. Common examples are parasitic wasps, entomophagus and competitive fungi and bacteria, predacious bugs, beetles and spiders. Natural enemies of pests exist everywhere in nature and should be conserved whenever possible. Many biocontrol organisms can be purchased for use in the greenhouse or for specific crops.
  • Pesticides should be used in conjunction with the control measures previously mentioned and only when pest population densities will cause economic damage, or when environmental conditions favor disease. Selective insecticides are products that primarily target the pest(s) you wish to control, with few or no detrimental effects on most beneficial organisms. They may also have other attributes making them less harmful to the user and the environment and may be lumped into a larger category of Biorational pesticides (see Biorational and Organic Pesticide section, page 74). If the use of a pesticide is required, choose a selective product or another biorational pesticide if possible. Selective insecticides usually spare biological control agents, reduce the risk of secondary pest outbreaks, reduce the impact on the environment, improve farm safety, and minimize the number of applications needed. Broad-spectrum insecticides usually kill many different kinds of pests and beneficial organisms. The use of broad-spectrum insecticides can often lead to resurgence of primary pest populations due to a lack of natural controls, or to secondary pest outbreaks and additional applications. Broad-spectrum insecticides should only be used if no other viable options exist to manage the pest. Proper pesticide application and resistance management techniques should be used to maximize the effectiveness and preserve the useful life of the available products.

Much of the space in this publication is dedicated to lists of pesticide options for weeds, insects and diseases on specific commodities. Effective pest management involves much more than using pesticides. Always review the summary paragraph(s) under each pest listing for preventative pest management methods and specific decision-making techniques before reaching for a pesticide. For detailed information on IPM, visit your local Extension System's IPM web site.

Abstaining from use of pesticides. Some growers choose to completely forgo the use of any kind of pesticides, be they conventional, biorational, or certifiably organic. While this strategy avoids possible detrimental effects to native natural enemies of pests and can save money on equipment and materials, it can lead to the buildup of very high populations of certain key pest species and disease inoculum. It may also affect neighboring farms by providing a sanctuary for local pest populations. 

Diagnostics for Plant Problems

Correct diagnosis of a problem and correct identification of the pest (insect, disease, abiotic factor, nutrition, etc.) causing the problem are key to successful crop management and profitability. Below is a list of laboratories that offer disease diagnostics on a fee-for-service basis. When submitting a sample, remember to specify whether you are looking for insect, disease, or weed (or other) identification in case more than one organism and/or symptom is present on your sample. Also, provide as complete a description of the problem as possible including crop, symptoms, distribution within field or greenhouse, and unique characteristics of the location. Commercial growers will receive different recommendations than home gardeners. Please indicate if you are an organic grower. In general, virus screening is limited to a small group of common viruses; further analysis is  referred to specialized laboratories. Contact your local  lab or your state Extension Vegetable Specialist for more information.

In order to submit a sample for diagnosis, some basic preparation instructions should be followed.

These include:

  • Collect specimens that show a range of symptoms (i.e., from healthy to seriously affected), usually collected from the margin of the affected area. Avoid specimens that are completely dead or decayed as they are not diagnostically useful.
  • Fill out the sample submission form (provided by lab). This is very important. Without detailed information about the problem, a correct diagnosis is very difficult.
  • Pack specimens in dry paper and place in a plastic bag (never pack with wet paper towels or add water).
  • Mail specimen and submission form using same-day or overnight delivery, or deliver specimen personally the same day. If this is not possible, place in a refrigerator and mail or deliver the following day. Specimens should come to the diagnostic labs early in the week to avoid problems with weekend holdovers.

Plant Diagnostic Clinics of New England

(D = plant disease identification, I = insect identification, N = nematode analysis, W = weed identification)

Connecticut

UConn Home & Garden Education Center (D,I,N,W)

Ratcliffe Hicks Building, Room 4
1380 Storrs Road, Unit 4115
Storrs, CT 06269-4115
(toll free) 1-877-486-6271
https://plant.lab.uconn.edu/
Cost:  $15

The Plant Disease Information Office (D,I,N, W)

The Connecticut Agricultural Experiment Station
123 Huntington Street, P.O. Box 1106
New Haven, CT 06504
www.ct.gov/caes
(203) 974-8601; (877)855-2237 toll-free outside New Haven area
Cost: free

 

Maine

Plant Disease Diagnostic Lab (D,I)

Pest Management Unit
17 Godfrey Drive
Orono, ME 04473-3692
1-800-287-0279 (within Maine) or (207) 581-3883 (outside Maine)  fax: (207)581-3881
www.extension.umaine.edu/ipm/ipddl
Cost: free to Maine residents (except for garlic nematode testing)

 

Massachusetts

Plant Disease Diagnostic Laboratory (D,I,N,W)

UMass Extension Plant Diagnostic Lab
#3 French Hall, 230 Stockbridge Road
Amherst, MA 01003
(413) 545-3208 fax: (413) 545-4385
http://ag.umass.edu/diagnostics
Cost: $50.00

 

New Hampshire

The Plant Diagnostic Lab (D,I,W)

UNH Plant Diagnostic Lab
38 Academic Way, G37 Spaulding Hall
Durham, NH 03824
(603) 862-3200 fax: (603) 862-2717

 

Rhode Island

University of Rhode Island Cooperative Extension Education Center (D,I,W)

URI Plant Protection Clinic
CE Education Center
3 East Alumni Avenue
Kingston, RI 02881
(401) 874-2900  fax: (401)874-2259
https://web.uri.edu/coopext/ppc/
Cost: $10

 

Vermont

University of Vermont Plant Diagnostic Clinic (D,I,W)

201 Jeffords Hall,
63 Carrigan Drive
University of Vermont
Burlington, VT 05405
(802) 656-0493 fax: (802)656-4656
https://www.uvm.edu/extension/pdc
Cost: $15 Vermont residents only

Pesticide Safety and Use

Who can apply pesticides

Farmers who use pesticides may require pesticide applicator licenses or permits according to state and federal law. It is important to check with your state lead agency (SLA) to determine what is appropriate in your state.  In general:

•    Farmers who apply restricted use pesticides on their crops need to have a private applicator license or permit.
•    Workers who help someone who is licensed or certified to apply restricted-use materials may also need a license to assist. 
•    Farmers who use only general use pesticides may also require licenses or permits; these requirements vary from state to state.
•    In most states, commercial (for hire) applicators must follow rules that are more restrictive than those of private applicators. 

Please note that the requirements of the EPA Worker Protection Standards (WPS) must still be followed regardless of whether a pesticide license or certification is required.  See the section below on WPS.  As of this printing, the following are contacts who can provide information on specific requirements for pesticide licenses and certification for each state.

Connecticut: 860-424-3369, http://www.ct.gov/deep/cwp/view.asp?A=2710&Q=324260
Maine: 207-287-2731, https://www.maine.gov/dacf/php/pesticides/applicators/licensing.html
Massachusetts: 617-626-1784, http://www.mass.gov/eea/agencies/agr/pesticides/
New Hampshire: 603-271-3640, http://agriculture.nh.gov/divisions/pesticide-control/index.htm
Rhode Island:  401-222-4700, http://www.dem.ri.gov/programs/agriculture/pesticides-regulatory.php
Vermont:  802-828-2431, https://agriculture.vermont.gov/public-health-agricultural-resource-management-division/pesticide-programs

Warning! Pesticides are poisonous.  Read and follow all directions and safety precautions on labels.  Handle carefully and store in original labeled containers out of reach of children, pets and livestock.  Do not use concentrations greater than stated on the label.  Do not apply more pesticide per acre or more frequently than the fewest number of days between applications recommended by the label.  Remember that the pesticide label is a legal document. If you do not follow the label directions implicitly, you could lose your applicator's license or be fined.

Pesticide Registration

Pesticides require both federal and state registration. Pesticides in this publication have been reviewed for federal registration status and are current at the time of publication. State registration status has been reviewed for most products, but state registrations are renewed annually and may be subject to change. Each New England state maintains a registration database, which can be found at the following websites:

Maine
Maine Board of Pesticides Control
http://npirspublic.ceris.purdue.edu/state/state_menu.aspx?state=ME
Searchable database

New Hampshire
Division of Pesticide Control
http://agriculture.nh.gov/divisions/pesticide-control/registration.htm
Contact Director of Division of Pesticide Control for information

Vermont
Vermont Agency of Agriculture, Food, and Markets
http://www.kellysolutions.com/vt
Searchable database

Massachusetts
Massachusetts Pesticide Product Registration Information
http://www.kellysolutions.com/ma
Searchable database

Connecticut
Connecticut Department of Energy and Environmental Protection
http://www.kellysolutions.com/ct
Searchable database

Rhode Island
Department of Environmental Management
http://npirspublic.ceris.purdue.edu/state/state_menu.aspx?state=RI
Searchable Database
Select 'Registered Pesticides' link for list
 

Understanding Pesticide Labels

A pesticide is referred to: (1) by a common name, which is also the name of the active ingredient (AI) or (2) by a trade or brand name (trade names are capitalized in this guide).  Trade names are used in the guide for identification only; no product endorsement is implied, nor is discrimination intended against similar materials.

Labels are for your protection and information: Look for the percentage (by weight) or amount of material in the formulation.  Compare costs of two similar products on the basis of effectiveness, the amount of actual pesticide contained and the quantity of the formulations needed/acre.

Labeled Formulations: The examples of pesticide products that are listed under each crop within this publication give only one formulation and one trade name.  Often there are other formulations and trade names with the same active ingredient. Growers should be aware of other formulations and products. Consult the tables in Disease, Insect, and Weed Management Sections (Tables 25, 26, and 27) for lists of formulations and products.  The rates to be applied are on the label.

  • Emulsifiable concentrates (EC) are less troublesome to spray equipment than wettable powders (WP). The water-based flowable concentrates and wettable powders are less likely to cause plant injury than oil-based concentrates of similar materials.
  • Wettable powders/suspendable powders (WP) are less likely than ECs to cause injury to sensitive plants or to cause trouble when mixed with fungicides or other pesticides.
  • Dry flowables (DF) are similar to wettable powders in their formulation but are pelletized to minimize dust.
  • Flowables (F) are liquid formulations with similar properties to latex paint. Clean equipment immediately after use.

NOTE: There may be several products registered with the same active ingredient.  Each label is different, and some crops may be listed on some labels but not on others.  Always be certain the crop is listed on the product label before ordering or using the product.

Restricted-Use Pesticides:  In accordance with federal and state pesticide regulations, those pesticides that are highly toxic and those that persist and accumulate in the environment are placed on a restricted-use list and shall be sold and used only by certified applicators.  For information about training for certified applicators contact your Extension Specialist or the offices listed above.  In some instances, states may require additional permits for certain pesticide users.

Control of target pest not on the label: Always be certain the crop is on the label before using a pesticide on that crop. Target pests not listed on the label may not be effectively controlled by that product.

Tank mixture and aerial application: Check the label and consult your state pesticide regulatory agency.

To avoid illegal residues: Adhere strictly to preharvest intervals. Accurately calibrate your equipment; never exceed label recommendations. Prevent drift to adjacent properties or crops, or contamination of bodies of water. The applicator is held responsible for problems caused by drift or contamination. High-volume, low-pressure, ground applications cause less drift than low-volume, high-pressure, air-blast, ground applications, aerial applications or dust.

Disposal of pesticides: Read label.  For current instructions on regulations and guidelines pertaining to the disposal of chemicals, contact your State Lead Agency (SLA) for pesticide regulation located in either the state Department of Agriculture or state Department of Environmental Protection. The Pesticide Stewardship Alliance (TPSA) has a pesticide disposal database with resources for each state. Visit their website at https://tpsalliance.org/resources/state-disposal-map/.  Triple rinse empty containers; dispose of them carefully and properly.

It is the responsibility of the user to read the label and be sure that the material selected is labeled for the proposed use.  Similar pesticide products may not have the same crop uses.

Pesticide Toxicity

All pesticides are poisonous.  However, some are more toxic than others.  The toxicity of the pesticide is usually stated in the precaution label.  For example, a skull and crossbones figure and the signal word "Danger" are always found on the label of highly toxic (Toxicity Class I) materials.  Those of medium toxicity (Toxicity Class II) carry the signal word "Warning".  The least toxic materials (Toxicity Class III) have the signal word "Caution".  The toxicity of a pesticide is expressed in terms of oral and dermal LD50.  LD50 (lethal dose 50) is the dosage of active ingredient that kills 50% of test animals (usually rats or rabbits) with a single application of the pure pesticide for a given weight of the animal (mg/kg of body weight).  The lower the LD50 value, the more toxic the material.  Oral LD50 is the measure of the toxicity of pure active ingredient when administered internally to test animals.  Dermal LD50 is the measure of the toxicity of pure active ingredient applied to the skin of test animals.  Generally, an oral application is more toxic than a dermal one.

The Worker Protection Standard and Who Must Comply

Pesticides can be useful tools for farmers.  They can also be deadly.  Exposure to pesticides can cause physical harm, debilitation, and even death.  Not only applicators are at risk.  Family members and workers can also be harmed due to improper storage and use of pesticides.  

For this reason, the EPA has developed the Agricultural Worker Protection Standard (WPS) for Pesticides (US EPA regulation, 40 CFR Part 170).  The WPS applies to all pesticides that are used in the production of agricultural plants on farms, forests, nurseries, and greenhouses.  This includes general use pesticides including those allowed in organic production (OMRI-approved), as well as restricted-use pesticides.  Also, even if a pesticide license is not required, employees and handlers must still receive education in and comply with the WPS.

The WPS requires the owner or employer to take steps to reduce the risk of pesticide-related illness and injury: 1) if pesticides are used on the farm or 2) workers or pesticide handlers are employed who may be exposed to such pesticides.

You will know a pesticide product is covered by the WPS if you see the following statement in the "Directions for Use" section of the pesticide labeling:

Agricultural Use Requirements

Use this product only in accordance with its labeling and with the Worker Protection Standard, 40 CFR Part 170. This standard contains requirements for the protection of agricultural workers on farms, forests, nurseries, and greenhouses, and handlers of agricultural pesticides. It contains requirements for training, decontamination, notification, and emergency assistance. It also contains specific instructions and exceptions pertaining to the statements on this label about personal protective equipment, notification of workers, and restricted-entry intervals.

The primary WPS resource is the How to Comply manual (http://pesticideresources.org/wps/htc/index.html), developed by EPA.  The manual is available from your State Lead Agency (SLA), pesticide education office of the Cooperative Extension Service, the EPA Region 1 office and EPA's National Agricultural Compliance Assistance Center.  Every agricultural producer should have a copy of the EPA How to Comply manual at https://www.epa.gov/pesticide-worker-safety/pesticide-worker-protection-standard-how-comply-manual

Key Elements of the Worker Protection Standard

The following is a brief summary of the major elements of the WPS.  Each of these categories is described in greater detail in the EPA How to Comply manual.  Producers should refer to the How to Comply manual for complete details and explanations of the requirements of the Worker Protection Standard.

Information and Education. To ensure employees will be informed about exposure to pesticides, the WPS requires:

  • Annual pesticide safety training for workers and handlers,
  • Pesticide safety poster to be displayed for workers and handlers
  • Access to labels and material safety data sheets for pesticide handlers and early-entry workers
  • Access to specific information in a centrally-located Application List of pesticide treatments on the establishment

Protection. To ensure employees will be protected from exposures to pesticides, the WPS requires employers to:

  • Prohibit handlers from applying a pesticide in a way that will expose workers or other persons
  • Exclude workers from areas being treated with pesticides
  • Exclude workers from areas that remain under a restricted entry interval (REI) with narrow exceptions
  • Protect early-entry workers who are doing permitted tasks in treated areas during an REI requirements include special instructions and duties related to correct use of Personal Protective Equipment (PPE)
  • Notify workers about treated areas so they can avoid inadvertent exposures
  • Protect handlers during handling tasks. Requirements include monitoring while handling highly toxic pesticides and duties related to correct use of PPE.

Mitigation. To mitigate exposures that employees receive, the WPS requires:

  • Decontamination sites that provide handlers and workers an ample supply of water, soap and towels for routine washing and emergency decontamination,
  • Emergency assistance that provides transportation to a medical care facility if an agricultural worker or handler may have been poisoned or injured by a pesticide and providing information about the pesticide(s) to which the person may have been exposed.

Agricultural Owner Exemptions. Even if you are the owner of the farm, forest, nursery, or greenhouse and you or members of your family do all the work there, you are a "WPS employer."  You must comply with SOME of the WPS requirements, such as adhering to restricted entry intervals, personal protective equipment (PPE) and ALL the specific requirements listed in the pesticide labeling.

If you hire commercial handlers, certain information must be given from you (the operator) to the commercial handler employer.

  • Specific location and description of any areas that may be treated with a pesticide or be under an REI while handler is there, or that the commercial handlers may be in (or walk within 1/4 mile of),
  • Restrictions on entering those areas.

Crop Advisors. The WPS requires employers to provide certain protections to their employees who are working as crop advisors. Examples of crop advisors are crop consultants, scouts, and integrated pest management monitors. An independent or commercial crop advisor is any person working as a crop advisor who is employed (including self-employed) by anyone other than the agricultural establishment on which the work is being done. Certain provisions of the WPS apply to crop advisors depending on when the advisor is on the farm and when the pesticide has been applied.

Commercial Handlers. Employers of commercial handlers must make sure that their customer the operator of the farm, forest, nursery or greenhouse, knows certain information such as: specific location and description of the area treated with the pesticide, time and date pesticide is to be applied, product name, EPA registration number, active ingredient(s), REI for the pesticide, whether the labeling requires treated area posting and oral notification and any other specific requirements on the pesticide labeling concerning protection of workers and other persons during or after application.

For more information on the WPS, contact your Cooperative Extension Pesticide Safety Education Coordinator, SLA or EPA Region 1 office, or visit https://www.epa.gov/pesticide-worker-safety/agricultural-worker-protection-standard-wps.

Pesticide Storage

Pesticides should always be stored in their original containers and kept tightly closed. For the protection of others, especially firefighters, the storage area should be posted as Pesticide Storage and kept securely locked.

Herbicides, especially hormone-like weed killers such as 2,4-D, should not be stored with other pesticides (primarily insecticides and fungicides) as they can volatize and be absorbed by other pesticides.

Store pesticides in a cool (40º-80º F), dry, well ventilated area that is not accessible to children and others who do not know or understand the safe and proper use of pesticides.

Any restricted pesticide or container contaminated by restricted pesticides must be stored in a secure, locked enclosure while unattended.  That enclosure must bear a "pesticide storage" warning sign readable at a distance of 20'.  If any pesticide has to be stored in other than its original container, that container must be labeled with the name and concentration of the active ingredient and the signal word and warning statements for the pesticide along with a copy of the label.  Keep an inventory of all pesticides stored in an area away from the storage site, so that it may be referred to in case of an emergency at the storage site.

Make available to personnel at all times: a respirator with chemical cartridge, gas mask with canister, goggles, rubber gloves and aprons, fire extinguisher and a detoxicant for spilled materials suggested by your local fire department.  Instruct all personnel on proper use of the above equipment and on what to do in case of emergency.  A shower stall with plenty of soap should be made available on the premises.  Prompt washing in case of accidental spillage may be a matter of life and death.

Keep your local fire department informed of the location of all pesticide storage areas.  Fighting a fire that includes smoke from burning pesticides can be extremely hazardous.  Firefighters should be cautioned to avoid breathing any smoke from such a fire.  A fire with smoke from burning pesticides may endanger people in the immediate area or community.  They may have to be evacuated if the smoke from a pesticide fire drifts in their direction.

Winter Storage of Pesticides. Plan pesticide purchases so that supplies are used by the end of the growing season.  When pesticides are stored for the winter, keep them at temperatures above freezing, under dry conditions and out of direct sunlight.  The following points should be observed:

  • Read the label.  Special storage recommendations or restrictions will be printed on the label.
  • Write the purchase or delivery date of the product on the label with waterproof ink.  Products may lose their effectiveness over several years.
  • Ventilation is important for storage of most pesticides.
  • Store herbicides separately from other pesticides to avoid cross contamination.  Below are signs of quality deterioration:

Formulation

General Signs of Deterioration

EC 

Evidence of separation of components such as sludge or sediment.  Milky appearance does not occur when water is added. 

Oils

Milky appearance does not occur when water is added. 

WP, SP 

Excessive lumping; powder does not suspend in water. 

D, G

Excessive lumping or caking 

After freezing, place pesticides in warm storage (50º-80º F, or 10º-26.7º C).  Shake or roll container every few hours to mix product or eliminate layering.  If layering persists or if all crystals do not completely dissolve, do not use product.  If in doubt, call the manufacturer.

Emergency Information

Human Exposure. If someone has swallowed or inhaled a pesticide or gotten it in the eye or on the skin:

  • Call 911 if the person is unconscious, having trouble breathing, or having convulsions.
  • Check the label for directions on how to give first aid.
  • Call the Poison Control Center at 1-(800)-222-1222 for help with first aid information.

The National Pesticide Information Center (NPIC) 1-800-858-7378 (http://npic.orst.edu/) can also provide information about pesticide products and their toxicity.

Poisoning Information (Adapted from Ohio Vegetable Production Guide). Make sure your doctor has a copy of the Note to Physicians that is placed on the labels of dangerous pesticides.

Treatment for pesticide poisoning is very precise. The antidotes can vary for the different pesticides. In an emergency, call your doctor and provide specific information on the trade name and common name of the pesticide exposed to. Your doctor will then consult the center if necessary.

Tables 25, 26, and 27 list restricted fungicides, insecticides, and herbicides that are commonly recommended for vegetable disease, insect, and weed control along with their oral and dermal LD50 values. Materials with an LD50 value of less than 100 should be considered highly toxic and handled with extreme caution.

Spills. The National Response Center can help you decide how to respond to a spill. They can be reached at: 1-(800)-424-8802. In addition, CHEMTREC maintains a large database of Material Safety Data Sheets, chemical information references, resources, and networks of chemical and hazardous material experts. CHEMTREC provides access to technical information regarding chemical products as well as telephone access to product specialists, chemists, or other experts. (1-800-262-8200 in the U.S. or 703-741-5500 outside the U.S.)

The Comprehensive Environmental Response, Compensations, and Liability Act (CERCLA) requires that all releases of hazardous substances (including radionuclides) exceeding reportable quantities be reported by the responsible party to the National Response Center (NRC). Title 40 of the Code of Federal Regulations Part 302 promulgates reportable quantities and reporting criteria. All the Extremely Hazardous Chemicals (EHS) that overlap with the CERCLA listed chemicals table (40 CFR Part 302.4) should be reported to NRC as well as to the LEPC and SERC.

For small pesticide spills or for more information, call the pesticide manufacturer or the National Pesticide Information Center (NPIC) at 1-800-858-7378. 

Reporting a Spill: The National Response Center (NRC) is the sole federal point of contact for reporting oil and chemical spills. If you have a spill to report, contact NRC at 202-267-2675 or 1-800-424-8802 (toll-free) or visit https://www.epa.gov/emergency-response/national-response-center for additional information on reporting requirements and procedures. Producers should be aware that they may be required to report spills to their state Lead Agency (SLA)  or their state Department of Environmental Protection.

Adjuvants

Adjuvants are non-pesticide chemicals that are added to pesticides or to pesticide spray mixtures to improve their chemical or physical characteristics.  The most common types of adjuvants are nonionic surfactants, crop oil concentrates, spreader/stickers, drift control agents, buffering agents, compatibility agents and foam-reducing agents.  Adjuvants can reduce or eliminate many spray application problems by performing specific functions.  These functions include spreading, wetting, sticking, reducing drift, buffering, improving compatibility, reducing foaming, and improving the effectiveness of certain pesticides.  Non-ionic surfactants are usually best for improving mixing of pesticides, for enhancing coverage of leaf surfaces, and for improving retention of the pesticide on the crop or weed.  Although several adjuvants perform more than one function, no one adjuvant can perform all of these functions.

The most important source of information you have to determine whether or not to use an adjuvant is the pesticide label.  Some prohibit the use of adjuvants due to the potential for severe crop injury or loss.  Surfactants can increase the potential for crop injury by enhancing penetration of pesticides into the foliage or by causing burning on their own.  High temperature and humidity enhance this potential injury.  Avoid spraying in the mornings or middle of days when you can add the temperature (º F) and % humidity together and get 150 or more.  

It is best to avoid silicone-based surfactants, ionic surfactants, or others that you are not familiar with unless you have a specific purpose for using them.  If a label does not list a certain tank mix that you want to use AND, at the same time, does not preclude it, you may make the tank mix.  Remember, however, that you should try it on a small scale first to make sure that there will be no problems.

Some labels provide no mention of adjuvants; in this case, consult the manufacturer or pesticide dealer.

Know Your Water

The pH of the water in your tank mix can sometimes affect the efficacy of pesticides.  Insecticides, in particular, have a tendency to break down (hydrolize) rapidly in alkaline water.  Water pH can vary, depending on the source, from 5.0-9.5.  Neutral water has a pH of 7.0, while alkaline water is higher than 7.0.  If your water pH is much higher than 8.0, you may want to consider using an acidifying agent such as vinegar to lower the pH in the tank.  Many of the pH-sensitive pesticides have acidifying agents in the formulation that moderate the effect of alkaline water.  However, growers who suspect a pH problem should have their water tested.  This can be done on the farm with pH test kits.  Also, organic matter can tie up certain pesticides or clog nozzles, so be sure to use water that is free of organic debris.

Selection of sprayer tips

The selection of proper sprayer tips for use with various pesticides is very important. Nozzle tips must be selected according to the spray coverage, droplet size, and application volume desired. Flat fan-spray tips are designed for preemergence and postemergence application of herbicides. These nozzles produce a tapered-edge spray pattern that overlaps for uniform coverage when properly mounted on a boom. Standard flat fan-spray tips are designed to operate at low pressures (30-60 psi) to produce small- to medium-sized droplets that do not have excessive drift.  Flood-type nozzle tips are generally used for complete fertilizer, liquid N, etc., and sometimes for spraying herbicides onto the soil surface prior to incorporation.

Full and hollow-cone nozzles deliver circular spray patterns and are used for application of insecticides or fungicides to crops where thorough coverage of the leaf surfaces is extremely important and where spray drift will not result in crop injury of nearby plants. They are used when higher water volumes and spray pressures are recommended. With cone nozzles, the disk size and the number of holes in the whirl plate affect the output rate. Various combinations of disks and whirl plates can be used to achieve the desired spray coverage.

Calibration for Field Sprayers

(Adapted from the Rutgers Commercial Vegetable Production Guide, https://njaes.rutgers.edu/pubs/commercial-veg-rec/pesticidesafety.pdf). Calibration is the process of measuring and adjusting the amount of pesticide your equipment will apply over a target area. Periodic calibrations of sprayers, dusters, and granule distributors are necessary to ensure accurate delivery rates of pesticides per acre. Calibrations are made by measuring the total gallons of water applied per acre, in the case of sprayers, and the total pounds of dust or granules applied per acre, in the case of dust and granule distributors. Too little spray or dust applied results in inadequate distribution of toxicant over plant surfaces. Control is usually poor, and additional applications are required. Too much per acre is hazardous for the applicator, is frequently injurious to plants (phytotoxic), and could lead to excessive residues if applied close to harvest.

Width of Boom. The width of boom must be expressed in feet. The boom coverage is equal to the number of nozzles multiplied by the space between nozzles.

Ground Speed (mph). Careful control of ground speed is very important for accurate spray application. Select a gear and throttle setting to maintain constant speed. A speed of 2-3 miles per hour is desirable. From a "running start," mark off the beginning and ending of a 30 second run. The distance traveled in this 30 second period divided by 44 will equal the speed in miles per hour.  Example: At a tractor speed of 1 mile per hour, you would travel 88'  in 1 minute, 44' in 30 seconds or 500' in 5 minutes and 41 seconds.

Sprayer Discharge (gpm). Run the sprayer at a certain pressure, and catch the discharge from each nozzle for a known length of time. Collect all the discharge, measure the total volume and convert the volume to gallons. Divide this volume by the time in minutes to determine discharge in gallons per minute. Catching the discharge from each nozzle checks the performance of the individual nozzle which is a critical step in calibration. If there is more than 10% variation between any nozzles, all the tips should be replaced. When it is not convenient to catch the discharge from each nozzle, a trough may be used to catch the total discharge.

Before Calibrating. Review and complete the following checklist:

1. Thoroughly clean all nozzles, screens, etc., to ensure proper operation.
2. Check to be sure that all nozzles are the same, are made by one manufacturer, and have the same part number.
3. Check the spray patterns of all nozzles for uniformity. Check the volume of delivery by placing similar containers under each nozzle. All containers should fill at the same rate. Replace nozzles that do not have uniform patterns or do not fill containers at the same rate.
4. Select an operating speed. Note the tachometer reading or mark the throttle setting. When spraying, be sure to use the same speed as used for calibrating.
5. Select an operating pressure. Adjust pressure to desired psi according to the nozzle manufacture. Do this while pump is operating at normal speed and water is actually flowing through the nozzles. This pressure should be the same during calibration and field spraying.

Calibration Using the Jar Method.  Any 1-quart or larger container, such as a jar or measuring cup, if calibrated in fluid ounces, can easily be used following the steps below. A specially designed calibration jar can be used; if you buy one, follow the manufacturer's instructions. Make accurate speed and pressure readings and jar measurements. Make several checks. Keep in mind that you are collecting less than a quart of liquid to measure an application rate of several gallons per acre for many acres.

1. Measure a course on the same type of surface (sod, plowed, etc.) and same type of terrain (hilly, level, etc.) as that to be sprayed, according to nozzle spacing as follows:

Nozzle Spacing  (in) 

16

20

24

28 

32

36 

40

Course length (ft)

255

204 

170

146

127

113

102

This area will be equal to 1/128 of an acre.

2. Time the seconds it takes the sprayer to cover the measured distance at the desired speed. Average several runs. This is the time required to cover 1/128 acre.
3. With the sprayer standing still, operate at selected pressure and pump speed. Catch the water from several nozzles for the number of seconds measured in step 2.
4. Determine the average output per nozzle in ounces. The ounces per nozzle equal the gallons per acre applied by one nozzle per spacing.

Calibration for Boom or Airblast Sprayer. The following applies to any pesticide that is applied as a liquid spray.

1. Fill sprayer with water.
2. Spray a measured area (width of area covered x distance traveled) at constant speed and pressure selected from manufacturer's information.
3. Measure amount of water necessary to refill tank (gallons used).
4. Multiply gallons used by 43,560, and divide by the number of square feet in area sprayed. This gives gallons per acre.
5. Add correct amount of spray material to tank to give the recommended rate per acre.

EXAMPLE:
Assume:
      10 gal of water used to spray an area 660 ft long and 20 ft wide
      Tank size - 100 gal
      Spray material - 2 lb formulated product/A

Calculation:
      gal used x 43,560       =       10 x 43,560       =        33 gal/A
          area sprayed                        660x 20                      
 
       tank capacity            
=        100 (tank size)   =        3.03 acres sprayed
           
gal/A                                   33                                 per tank
 
       3.03 x 2 (lb/A) = 6.06 lb material per tank

Calibration for Granular Applications

The application equipment for granular fertilizer, herbicides, insecticides, etc. in many cases was not designed as precision equipment; therefore, extra care must be taken in calibration to get the results desired. Application rates of granular application equipment are affected by several factors: gate openings or settings, ground speed of the applicator, shape and size of granular material, and roughness of the ground. It takes a conscientious operator, effort, knowledge of equipment, and calibration to achieve accurate application rates. The first step to good application is to be sure the equipment is prepared for operation. Be sure all controls are free and work properly. Check and lubricate moving parts as necessary, remove corrosion, and tighten loose nuts and bolts.

Broadcast Applicators (Gravity-Drop or Spinner Applicators)

1. From the label, determine the application rate.
2. From the operators manual, set dial or feed gate to apply desired rate.
3. On a level surface, fill hopper to a given level and mark this level.
4. Measure test area - length of run will depend on size of equipment. It need not be one long run but can be multiple runs at shorter distances.
5. Apply material to measured area, operating at the speed applicator will travel during application.
6. Weigh amount of material required to refill hopper to the marked level.
7. Determine application rate:
                                                 number    x        length of      X       width of
      Area covered      
=              of runs ______  run (ft)________application (ft)
           (acres)                                                       43,560

 

     Application    =       amount applied (pounds to refill hopper)   
        rate (lb/A)                          area covered (acres)                             

NOTE: Width of application is width of the spreader for drop or gravity spreaders. For spinner applicators, it is the working width (distance between runs). Check operator's manual for recommendations, generally one-half to three fourths of overall width spread.

EXAMPLE:
Assume: 50 lb/A rate
              Test run-200 ft
              Four runs made
              Application width-12 ft
              11.5 lb to refill hopper
                            
      Area covered    =  4 x 200 x 12     =     0.22A
                                      43,560

      Application rate =      11.5              =     52.27 lb/A
                                        0.22

8. If application rate is not correct, adjust feed gate opening and recheck.

Calibration for Band Applicators

1. From the label, determine application rate.
2. From the operator's manual, determine applicator setting and adjust accordingly.
3. Fill hopper half full.
4. Operate applicator until all units are feeding.
5. Stop applicator; remove feed tubes at hopper.
6. Attach paper or plastic bag over hopper openings.
7. Operate applicator over measured distance at the speed equipment will be operated.
8. Weigh and record amount delivered from each hopper. (Be sure all hoppers and all tubes deliver the same amount.)
9. Calculate application rate:

Area covered in bands (acres) = 

      number                     length of                        band
     of bands       
           run (ft)           x           width (ft)
                                              43,560

Application rate:

     Rate applied in bands (lb/A)      =     total amount collected (lb)
                                                            area covered in bands (acres)

10. If not correct, readjust and recheck.

Calibration for Changing from Broadcast to Band Application.  Within a field, the treated area may be only a fraction of the total land area. Calculate application rates for portion of the field that is treated, using the ratio of band width to row spacing, as follows:

   Band width                      broadcast                              amount needed
   __in inches              x          rate                    
=                    per acre                              
   row spacing                      per acre                                        of field
       in inches

Calibration for Backpack Sprayers

Growers with diverse crops and small plantings often need to be able to apply pesticide to beds or plots of several hundred square feet. It is important to use the correct amount of pesticide in your backpack sprayer when spraying a small area, to mix and spray safely, and to follow the label instructions.

All measuring and mixing utensils used with pesticides or other chemicals should be clearly labeled with warnings that they are only to be used for measuring and mixing pesticides. Measuring equipment should be locked in the pesticide storage area. All equipment calibration should be done on the same surface to which the pesticide will be applied and at the same speed, pressure, etc.

Maintaining constant pressure can be difficult with sprayers that depend on continual hand pumping. To help with backpack sprayer calibration and application, constant flow nozzles are available.  G.A.T.E. LLC manufactures a CF Valve that delivers a constant 14.9 psi recommended for spraying herbicides and a 21 psi for insecticides and fungicides.  These are designed to deliver the same pressure and flow rate no matter what the pressure in the tank is above the designated pressure and shut off if the pressure in the tank falls below the designated pressure.  SOLO makes a "pressure limiting valve" that actually has three settings of 5, 10 and 15 psi for their backpack sprayers that does the same thing. 

Calibration will vary with the crop, crop stage, amount of canopy, and location of target pest in the crop. Seedlings will require far less material than a fully grown canopy. Match the amount of pesticide to the amount of water needed to spray the crop area at the target crop stage.

For products with rates listed in amount/acre: 

1. Calculate what portion of an acre is being sprayed. Determine sq ft of area to be sprayed (multiply bed or canopy width by row length by number of rows). Calculate what proportion of an acre this is (it may be a small fraction of an acre):

     Proportion of an acre to be sprayed     =     number of sq ft. to spray

                                                                         43,560 sq ft. per acre

2. Calculate how much pesticide to use.  Multiply the label rate per acre for the crop and pest times the proportion of an acre to be sprayed.   

     Amount of pesticide needed      =      amount per acre      X     proportion of acre to be sprayed

3. Measure water needed per sq. ft. of crop. Add a known amount of water (eg 1 or 2 gallons) to the tank. Spray the water as if you were actually spraying your field. Remember, you must maintain constant pressure, constant walking speed, and consistent nozzle height and boom setup or wand motion to achieve the coverage you need. This amount will change with different crops and size of crop canopy. When the water is gone, stop and mark the spot. Measure the area you sprayed and calculate square feet (length of swath x width). Calculate how many gallons (or fluid ounces, for smaller areas) needed per sq ft.

      Gallon per sq ft     =      number of gallons used    

                                          number of sq ft sprayed

This can also be calculated by timing how long it takes to spray a known area, then collecting the output for the same amount of time, at the same pressure. Divide the amount used by the area sprayed. 

4. Determine total water needed:

     Gallons of water needed     = gal. per sq ft        X      number of sq ft to be sprayed

5. Mix the required amount of pesticide in required amount of water. Most commonly, it is best to add half the water, add the pesticide, agitate, then add the remaining water. Spray, using the walking speed, pressure, nozzle and boom setup or wand motion that you used for calibrating. 

For products that give rates for backpack sprayers: Some pesticide label provide a rate of product to use per gallon, for backpack sprayers or smaller areas. If this is given, it is still important to calibrate to determine the amount of water used per unit area (sq. ft.).  Add the labeled rate pesticide per gallon of water, adjusting the rate to match the fraction or number of gallons that will be used.

Protecting Groundwater and Surface Waters

There is considerable public concern about water quality, and agriculture is coming under increasing scrutiny regarding practices that can affect water quality. Many pesticides and fertilizers are soluble in water and can leach through the soil to contaminate underlying groundwater. Several factors affect the movement of chemicals in the soil and their likelihood of reaching groundwater. Consideration of these factors can minimize the threat to groundwater.

Pesticide Characteristics:

Solubility is the ability of a chemical to dissolve in a solvent.  Pesticides that are highly soluble in water are often desirable from an applicator's perspective because they are less likely to clump and/or separate.  However, they also pose potential water quality issues as they can easily leach into the groundwater supply.  If practical, to reduce leaching potential select the least soluble material and use the lowest effective rate.

Adsorption is the binding of a chemical to the surfaces of soil particles and organic matter. Some chemicals are tightly adsorbed and do not easily leach from soils; however, they have a higher risk of moving with soil when there is surface erosion. Others have low adsorption, and will leach more easily.

Persistence refers to the amount of time a chemical will stay in the environment before being broken down into nontoxic substances.  The rate of breakdown is affected by sunlight, temperature, soil pH, moisture and microbial activity.  Pesticide persistence is measured in terms of half-life, which is the length of time needed for one-half of the amount applied to break down.  Persistent chemicals break down slowly, increasing the chance for them to leach into the soil.  Conversely, short-lived materials may be degraded before significant leaching occurs.  Many pesticides are broken down by sunlight (photodegradation) and/or microbial action. Incorporation of pesticides into the soil reduces or eliminates photodegradation.  As depth in the soil increases, there is less microbial degradation.  Any practice that slows degradation increases persistence and the likelihood of leaching.  Generally, foliar applied materials are more likely to break down before significant leaching occurs than those that are applied to the soil.

Soil Characteristics and Topography: Soil texture and organic matter greatly influence the movement of pesticides and fertilizers. Fine textured soils and those with high amounts of organic matter are highly adsorptive, whereas sandy soils low in organic matter are not. Highly permeable soils with permeable underlying layers allow for rapid downward movement of water and dissolved chemicals. Steep grades and long slopes allow water to build up speed and carry soil and contaminants off-site. Know your soils and apply chemicals accordingly.

Water Table: High water tables are especially vulnerable to contamination because little time is required for chemicals to reach groundwater. Tile drainage allows contaminants to leave the field faster and enter surface waters directly through outlet pipes. Excessive precipitation or irrigation, or poorly timed irrgation, immediately after pesticide or fertilizer applications, can also move contaminants off-site and into surface and ground water quickly.

Contact Cooperative Extension and the Natural Resource Conservation Service about questions you may have regarding the use of certain pesticides on your soils.

Leachable pesticides: The following are some pesticides used on vegetables that have been identified as having high leaching potential:

  • alachlor (Lasso)
  • atrazine (Aatrex)
  • bentazon (Basagran)
  • chlorothalonil (Bravo)
  • DCPA (Dacthal)
  • methomyl (Lannate)
  • metolachlor (Dual)
  • metribuzin (Sencor/Lexone)
  • simazine (Princep)  

Biorational and Organic Pesticides

Pesticides vary in their toxicity to people and to non-target organisms, and in their potential ecological impact. Pest control materials that are relatively non-toxic to people with few environmental side-effects are called “biorational” pesticides in this Guide. Biorational pesticides mostly include the following categories further defined in this section: biopesticide, organic pesticide, minimum-risk pesticide, and biological control. Federal law governs pesticide registration through the EPA, and materials derived from living things are defined as “biopesticides”. Organic production is regulated through the USDA National Organic Program which defines what inputs are allowed for pest management. “Organic” and “biopesticide” are partially overlapping categories, and each is defined by specific criteria that are unique. “Minimum risk pesticide” is another category that is defined by EPA; these are exempt from federal registration. “Biological control” describes living organisms that suppress pests. Some biological controls are naturally occurring, some are insects purchased by farmers for pest control, and some are microbes formulated for sale as biopesticides.

All tables in this section include products that are registered as pesticides as well as some that are exempt from EPA registration. None are federally restricted-use products. Most have low dermal and oral LD50 values and they carry the minimum EPA signal word of “Caution”. However, some organic pesticides such as copper sulfate have a high dermal and oral LD50 value and carry the EPA signal word “Danger” on their label.

Types of Biorational Pesticides

Botanicals are plant-derived materials such as pyrethrin, azadiractin, and extracts of plants such as Chenopodium ambrosioides and Swinglea glutinosa. Plant-derived oils such as neem oil, canola oil, and sesame oil are also included in this group. Botanicals are generally short-lived in the environment, as they are broken down rapidly in the presence of light and air. Products generally have low mammalian toxicity and a broad spectrum of activity. Many botanicals are considered minimum risk pesticides and are exempt from registration by EPA (see below).

Microbial pesticides are formulated from living microorganisms and/or their by-products. Microbial insecticides tend to be selective, so specific pests may be controlled with little or no effect on non-target organisms, while most microbial disease control products have a wider spectrum of activity. Microbial insecticides may be derived from bacteria (e.g. Bacillus thuringiensis, spinetoram and spinosad, Chromobacterium subtsugae), virus (e.g. nuclear polyhedrosis virus of corn earworm) or fungi (e.g. Beauvaria bassiana).  Microbial disease control products are living organisms, including beneficial fungi and bacteria. Examples of microbial disease control organisms are the fungus Trichoderma harzianum and the bacterium Bacillus subtilis. While these active ingredients are generally approved for organic production (OMRI listed) because of their natural origin, certain formulated products are prohibited because the inert ingredients or procedures used in making the product are prohibited.

Minerals. Some pesticides made from minerals, mined from the earth and minimally processed, are allowed in organic production.  Kaolin clay, copper hydroxide, and iron phosphate are examples (see Table 21, page 76, and Table 23, page 79).

Synthetics. Minerals and other natural materials that are heated, chemically reacted, or mixed with surfactants may be considered synthetics. Synthetics also include insect growth regulators (IGR), which interrupt or inhibit the life cycle of a pest. They may also work by strengthening plant defenses. National organic standards include some allowed synthetics.

Biopesticides

Biopesticides, as defined by EPA, are certain types of pesticides derived from such natural materials as animals, plants, bacteria, and certain minerals. As of April 2016, there are 299 registered biopesticide active ingredients and 1401 active biopesticide product registrations. EPA generally requires less data to register a biopesticide than to register a conventional pesticide, thus the registration process is faster.  Categories of biopesticides include:

  • Microbial pesticides, in which a microorganism (e.g., a bacterium, fungus, virus or protozoan) is the active ingredient
  • Plant-Incorporated-Protectants (PIPs), in which pesticidal substances are produced by crop plants as a result of genetic material being added to the plant (e.g., Bt insecticidal protein)
  • Biochemical pesticides, which are naturally occurring substances that control pests by non-toxic mechanisms, such as sex pheromones that interfere with mating and scented plant extracts that attract insect pests to traps. With plant-incorporated protectants, the toxin and its genetic material, but not the plant itself, are regulated by EPA.

Biopesticides generally fit well into an integrated pest management (IPM) strategy, which relies on monitoring for early detection of pests and emphasizes the use of selective products that protect crops while minimizing negative effects on water, air and soil, and on pollinators and beneficial insects.  The purpose of this section is to bring these types of products together to help growers make decisions about pesticides and biological controls to use on their farm.

Pesticides in Organic Production

The USDA National Organic Program allows application of biological, botanical, or mineral inputs, when cultural practices are insufficient to prevent or control crop pests, weeds, and diseases. Most of these are non-synthetic and/or minimally-processed.

NOTE: not all biopesticides are labeled for use in certified organic agriculture. The grower is responsible for determining whether materials are allowed under organic standards.  Sometimes this may be a challenge because some materials labeled as organic by the manufacturer may not actually be allowed by the USDA National Organic Program.  The Organic Materials Review Institute (OMRI) is recognized by the National Organic Program as an organic material review organization.  It lists products it finds suitable for certified organic production.  These products are generally allowed without restriction, but some are regulated and subject to restrictions. In some cases, OMRI notes that certain formulations of a product are permitted and others are not. The list of substances approved by OMRI is subject to change.

Be sure to check with your certifier in advance to be certain that the materials and practices you plan to use are approved by your certifier, and that you understand any restrictions on use. For the most up-to-date OMRI list, visit the OMRI web site at: www.omri.org. When mentioned in tables or in crop chapters, this Guide designates approved organic materials with a superscript OG ( OG ), which means they were "OMRI listed" at the time of publication (June 2022).

Minimum risk (exempt) pesticides

These are a special class of pesticides that are not subject to federal registration requirements because their ingredients, both active and inert, are demonstrably safe for the intended use. This exemption falls under section 25(b) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). Of the New England states, CT, ME, NH, RI and VT all require state registrations for these products while MA allows exemption for all products that meet the minimum risk criteria and are on the federal 25(b) list.  For more information, please contact your state's pesticide registration office (see Pesticide Safety and Use, page 67). The list of 25(b) exempt materials includes the following: corn gluten meal; sodium chloride; corn, linseed, sesame, soybean, and cottonseed oil; garlic and garlic oil; and essential oils including rosemary, mint, thyme, geranium, lemongrass, cinnamon and rosemary. Some pest control products listed in this guide meet the criteria for exemption and do not have EPA pesticide registration or a pesticide label. More on this class of pesticides can be found at: https://www.epa.gov/minimum-risk-pesticides.

Biological Insect Control

Biological control is taking place in vegetable crops all the time, because native and naturalized populations of natural enemies overwinter on the farm and move into crops to feed on or lay their eggs into pest insects. Predators consume several insects over the course of their development. Parasites (also called parasitoids) lay eggs in their host insect, which hatch into larvae that feed internally, develop, and kill the host. Pathogens invade the body of the host insect. The impact of beneficial insects is often underestimated because it is easy to overlook and difficult to measure. Beneficial insects may be killed by broad-spectrum insecticides, and pest outbreaks can occur as a result. Conservation of beneficials by use of selective insecticides when pests exceed threshold levels is recommended wherever practical.

The release of commercially produced beneficials can also aid in suppressing pests. These tend to be more successful in greenhouses than in the field, but there are several instances where releases in the field have been proven to suppress or completely control key pests. Trichogramma are tiny wasps that lay their eggs inside the eggs of insects, and wasp larvae develop inside, killing the egg. Several species are commercially available, but the most useful in vegetable crops are T. pretiosum for caterpillar eggs and T. ostriniae against European corn borer in sweet corn and pepper. Releases should be timed to coincide with egg laying. See Table 22 (page 78) for information about biological controls for the field, and also Biological Control for Insects and Mites in the Vegetable Transplants section.

Biological Disease Control

Biological disease control products (fungicides, bactericides, and nematicides) fall into the same classes as the insecticides. Botanicals, minerals, and synthetics are listed in Table 23 (page 79). Sulfur, potassium bicarbonate, phosphites, and copper compounds are examples of minerals or synthetics that can control fungal and bacterial diseases. Not all of these products are OMRI listed; be sure to check with your state certifying authority for more information on these materials. Botanicals such as rosemary oil, soybean oil, or garlic extracts also appear in this table and are generally approved for use in organic production by OMRI. Products listed in Table 23 (page 79) require thorough coverage, application at the first signs of disease, and frequently repeated dosages to be effective. For products that may be used in vegetable transplant production, see Table 19 (page 54).

Microbial products are listed in Table 24 and are all living organisms which require specialized storage and application procedures. The table includes beneficial fungi and bacteria such as Streptomyces, Gliocladium, and Trichoderma, which compete with plant pathogens, produce toxic metabolites, or actively parasitize pathogens. Their effectiveness in university research trials has been inconsistent because of variations in environmental conditions and disease pressure. Microbial disease control products perform best in a greenhouse environment where they can establish and flourish. Control of plant pathogenic organisms on the phylloplane (leaf surface) is especially problematic, as the competing organisms must establish themselves and can fail due to desiccation and exposure to sunlight. These materials have a limited shelf life, must be protected from temperature extremes, and correctly applied (plenty of water and under the correct environmental conditions) for effectiveness.

 

Table 21: Biorational and Selective Insecticides and Miticides

This table includes products that are registered as pesticides as well as some that are exempt from EPA registration.  Most have low toxicity to bees and beneficial insects. None are federally restricted-use products. Most have dermal and oral LD50 values over 2,000 mg/kg (see Table 27 and 28 for LD50 values for insecticides and fungicides). Selective insecticides have efficacy on specific insect groups, or a specific life stage, and are therefore safe for non-target beneficial insects.

Active Ingredients Trade Name Target Pests Comments
azadiractin Amazin Plus 1.2%MEOG; Aza-DirectOG; AzaGuardOG, Azatin OOG; XL; Azatrol ECOG; AzeraOG(M); Ecozin Plus 1.2%MEOG; Molt-XOG; Neemix 4.5OG, Ornazin 3%EC Aphids, caterpillars, leafhoppers, leafminers, thrips, whiteflies, beetles, and other insects An insect growth regulator extracted from the seeds of the neem tree. works by contact or ingestion against immature stages, and has antifeedant properties.
Bacillus thuringiensis subsp. aizawai

XentariOG

Caterpillars, as listed for Bt kurstaki, as well as cross-striped cabbageworm, armyworms, cutworm

Use in rotation with Bt kurstaki products to prevent resistance. May be used in greenhouse or field.
Bacillus thuringiensis subsp. israelensis Gnatrol WDGOG Fungus gnats For use in greenhouse.
Bacillus thuringiensis subsp. kurstaki CoStarOG; DeliverOG; Dipel ES, Dipel DFOG; Javelin WGOG Many caterpillars, including cabbage looper, diamondback moth, imported cabbageworm, European corn borer, hornworm Must be ingested. Apply when caterpillars are actively feeding. Safe on beneficial insects. For some species, more effective on smaller larvae.
Bacillus thuringiensis subsp. tenebrionis strain SA-10 TridentOG Colorado potato beetle For use on potato, tomato, and eggplant. Must be ingested. (Trident currently unavailable due to formulation and shipping issues)
buprofezin

Talus 70DF

Leafhoppers, mealybugs, planthoppers, whiteflies Insect growth regulator.
Burkholderia spp. (heat-killed) Strain A396 and spent fermentation media Venerate XCOG, Majestene OG Caterpillars, cutworms, aphids, mites, thrips, whiteflies Works by contact and ingestion to disrupt insect exoskeletons and interfere with molting.
capsicum oleoresin extract, garlic oil, soybean oil Captiva Caterpillars, mites, thrips, leafhoppers, whiteflies Has anti-feedant, anti-egg laying, and irritant activity, and weakens cuticles of immature stages of insect and mite pests.

Chenopodium ambrosioides extract

Requiem

Aphids, whiteflies, thrips, leafminer, mites

Contact insecticide/acaricide. Can be applied for ovicidal control. Start when populations are at threshold. Compatible with beneficial insects.

chlorantraniliprole Coragen Caterpillars, Colorado potato beetle, leafminers May be used as soil or transplant water treatment at planting, in drip or as foliar. Avoid run-off in surface waters. Non-toxic to bees.
Chromobacterium subtsugae strain PRAA4-1 GrandevoOG Caterpillars, aphids, whiteflies, mites, leafhoppers, thrips A selective biological insecticide/miticide containing fermentation solids. Works as a stomach poison upon ingestion. No systemic activity. Toxic to bees exposed to direct treatment or residues on blooming crops or weeds.
clarified hydrophobic extract of neem oil Triact 70OG, TrilogyOG Primarily labeled for (but not limited to) mite control Can be used to control mites. For best results use when population levels are low to prevent build-up. Repeat applications are needed.

clove oil, thyme oil and cinnamon oil

Ecotrol G2OG

Root maggots, wireworm, cutworm, Symphylans

Soil-incorporated volatile plant oils on a corn cob carrier, applied before, during or after planting. Exempt from registration and reporting under Federal EPA standards. 

cryolite Prokil Cryolite 96 Colorado potato beetle (larvae only), cucumber beetle, flea beetle, cutworms, some caterpillars Stomach poison, must be ingested. Sodium aluminofluoride mineral, applied as spray or dust. Reapply to cover new growth. May cause extensive wear of nozzles.
cyromazine Trigard Leafminer, Colorado potato beetle An insect growth regulator.
diflubenzuron Dimilin Armyworms, pepper weevils A selective insect growth regulator that disrupts the molting process of insect larvae.
etoxazole Zeal Mites A mite growth regulator that works as an ovicide and larvicide.
flonicamid Beleaf Aphids, plant bugs, whiteflies A pyridinecarboxamide that works by contact and ingestion. Feeding stops rapidly and mortality will follow.
flubendiamide (Note: All flubendiamide registrations were canceled by the EPA in 2016. Growers may use up existing stock.) Belt SC  Caterpillars including armyworms, loopers, hornworm, corn earworm,  European corn borer A diamide, active by insect larval ingestion, leading to a rapid cessation of feeding followed by death. Labeled for use as a foliar spray on Brassicas and turnip greens, leafy vegetables, sweet corn, cucurbits, fruiting vegetables, and legumes to control caterpillars.
flupyradifurone Sivanto Aphids, leafhoppers, whiteflies, Colorado potato beetles, squash bugs A broad-spectrum insecticide in a new class of chemistries, the Butenolides. Acropetally systemic, and translaminar. No toxicity to bees in lab tests.
insecticidal soap (Potassium salts of fatty acids) Des-XOG, M-PedeOG Aphids, leafminers, mites, thrips, whiteflies Works on contact. Can be phytotoxic to some crops, test on small plot. Avoid treatment when plants are stressed. May also harm some beneficials. Also active against powdery mildews.
iron phosphate Sluggo: Snail and Slug BaitOG Snails, slugs Bait which causes feeding to cease. Death occurs over 3-5 days. Exempt from tolerance and has a zero hour re-entry interval due to low toxicity to people and wildlife.
kaolin Surround WPOG Flea beetle, striped cucumber beetle, leafhopper, thrips Interferes with insects' ability to recognize their host; particles cling to cuticle. Plant leaves turn white but growth is not inhibited. Reapply after heavy rain. To avoid lumps in mixing, form a slurry, then dilute. Maintain agitation.
metaldehyde Deadline Bullets Slugs, snails A toxic bait. Not for direct application to or contamination of edible portions of the plant; to be applied as a band treatment between rows after formation of edible parts. Long-lasting; resistant to rain and watering.
methoxyfenozide Intrepid Many species of caterpillars Mimics molting hormone; causes premature molt and death.
novaluron Rimon Caterpillars, beetles, leafminers, squash bugs, thrips, whiteflies An insect growth regulator for use on immature stages.
petroleum oil (mineral, parrafinic oils) JMS Stylet Oil, Organic JMS Stylet OilOG, Suffoil XOG aphids, leafminers, beetle larvae, mites, thrips, leafhoppers, whiteflies A horticultural oil (80% petroleum oil) insecticide, miticide and fungicide. Kills eggs, larvae and nymphs of insects and mites and adults of soft-bodied insects through suffocation. Registered for use as a foliar spray on a variety of crops. Also labeled for certain diseases.
pymetrozine Fulfill Aphids Works by contact and ingestion, translaminar with long residual.
pyrethrin PyGanic EC5.0IIOG, PyGanic EC1.4OG Asparagus beetle, blister beetle, cucumber beetle, flea beetles, Mexican bean beetle, potato leafhopper, many caterpillars, aphids, stink bugs Botanical insecticide with broad-spectrum activity. Contact toxin with rapid knockdown but short period of activity (non-persistent). Highly toxic to fish. Derived from a chrysanthemum species cultivated in Africa. Some formulations are approved for organic crops.
pyriproxyfen Esteem, Distance IGR, Knack Thrips, whiteflies shoreflies, fungus gnats Label may include greenhouse or field use. An insect growth regulator that suppresses development of embryo within the egg, immature, and pupal stages of the insect. No activity against adult insects.

rosemary oil, peppermint oil, other essential plant oils

Ecotrol PlusOG

Aphids, beetles, bugs, early stages of caterpillars, leafminers, mites, thrips

Works on contact as an insecticide and miticide. Greenhouse and field use. Thorough coverage is needed. Exempt from registration under Federal EPA standards.

soybean oil

Golden Pest Spray OilOG, Captiva

Primarily soft-bodied insects A soybean-derived horticultural oil that works as a contact insecticide, as well as a feeding and oviposition deterrent. Exempt from registration under Federal EPA standards.

spinetoram

Radiant

See spinosad, below.

A second-generation spinosyn, similar to spinosad, below.

spinosad Blackhawk, EntrustOG, Seduce Insect BaitOG, GF-120 NaturalyteOG Caterpillars, Colorado potato beetle, asparagus beetle, flea beetle, leafminers, thrips. Baits labeled for cutworms, earwigs (Seduce) or fruit flies (GF-120) Acts both as a contact and stomach toxin. Derived from soil bacterium Saccharopolyspora spinosa. Non-disruptive to most predator insect species and some parasites. Rotate with other selective biorationals to prevent resistance. 
spiromesifen Oberon Whiteflies, nymphs & pupae, mites Contact insecticide and miticide.
sulfur Microthiol DisperssOG Mites Micronized wettable sulfur, also labeled as a fungicide.
tebufenozide Confirm Caterpillars Selective insect growth regulator.
The symbol OG indicates a pesticide that has been listed by the Organic Materials Review Institute (OMRI) as compliant with the National Organic Standards and therefore approved for use in organic production.

 

Table 22: Biological Controls for Insect Pests

The products and living organisms listed in this table suppress pests on vegetable farms. Some biological controls are naturally occurring, some are insects purchased by farmers for pest control, and some are microbes formulated for sale as biopesticides.  Most are exempt from EPA registration, and most are allowable for organic production.

Part 1. Established beneficial insects that live on New England farms

Scientific name Common Name Target Pests Comments
Chrysopa and Chrysoperla spp. Green lacewings Aphids, thrips, mites, whiteflies, leafhoppers, small caterpillars, insect eggs Larvae feed voraciously on many small insect pests. Common throughout the US, and available commercially.
Coleomegilla maculata Twelve-spotted ladybeetle Aphids, small caterpillars, small beetle larvae, insect eggs Native to North America. Both adults and larvae are predators. Wide range of prey and of crops and habitats. Feeds on newly hatched larvae as well as insect eggs. Also eats pollen.
Cotesia congregatus Braconid wasp Tomato hornworm Parasitic wasp that lays eggs in hornworm caterpillars.
Cotesia rubecula Braconid wasp Imported cabbageworm (ICW) Parasitic wasp that lays eggs in small ICW. Exits and spins oval, white cocoon. Introduced to New England in 1988; now well established.
Harmonia axyridis Multicolored Asian ladybeetle Aphids Adults have many variable markings. Both adults and larvae are predators. Renowned for invading homes in fall. May be a pest of grapes. Introduced to North America; widespread range.
Orius insidiosus Insidious flower bug Aphids Commonly found in corn. Small (3 mm).
Podisus maculiventris Spined soldier bug Beetle larvae, caterpillars, insect eggs, aphids Prey includes Colorado potato beetle. Both adults and nymphs are predators. Uses piercing sucking mouthparts to feed on soft-bodied insects.
Syrphid species Syrphid fly larva (immature of hover fly) Aphids, small caterpillars Adult hover flies (Syrphids) mimic bees and feed in flowers. Immatures are voracious aphid predators; legless, cream or brown in color, found in aphid colonies.

Part 2: Biological control organisms, released or applied to crops

Scientific name Common Name Target Pests Comments
Beauvaria bassiana Strain GHA Mycotrol ESO, Botanigard Aphids, whiteflies, thrips, Colorado potato beetle This fungus penetrates the insect cuticle, fills its body, kills it, and releases more spores. Apply in the evening and target coverage of lower leaves, as spores are inactivated by sunlight. Use preventatively based on monitoring, before pests reach high levels. Can be tank mixed with other microbials for Colorado potato beetle.

Isaria fumosorosea Apopka Strain 97 (formerly Paecilomyces fumosoroseus)

PFR-97OG, PreferalOG aphids, mites, thrips, whiteflies, leafminers, rootworms, wireworms, grubs, caterpillars A naturally-occurring fungus that penetrates the cuticle of insect pests.
Metarhizium anisopliae Strain F52 Met 52EC thrips, whiteflies, mites Composed of spores of a naturally occurring insect pathogenic fungus. Spores attach to the insect and hyphae penetrate the exoskeleton, growing inside and causing death in 3 to 7 days. Labeled for use as a foliar spray or soil drench on field and greenhouse onions to control thrips, and on field and greenhouse celery, lettuce, spinach, peppers, and tomatoes to control thrips, whiteflies, and mites. Persistence will generally be higher when incorporated into soil, but may be effective for a few months even in foliar applications.
Pediobius faveolatus No common name Mexican bean beetle Small parasitic wasp of the Eulophid family, which attacks larvae of the Mexican bean beetle. Releases should be timed to coincide with egg hatch because wasps lay eggs in young larvae, which are then killed and form a pupal case, or 'mummy' from which a new adult wasp will emerge.
Steinernema and Heterorhabditis species Beneficial nematodes Cutworms, white grubs, wireworms, maggots, beetle larvae, soil-dwelling adult insects Nematodes are very small roundworms. Some species are plant pathogens, but some attack soil-dwelling insects and two in particular (Steinernema and Heterorhabditis) have been mass-reared for commercial use. These seek out and penetrate their host insects, multiply within the host and kill it. They are most likely to be effective against the soil-dwelling immature stages of susceptible hosts. Nematodes require moist soil conditions to survive.
Trichogramma ostriniae No common name European corn borer

Tiny parasitic wasp that oviposits in the eggs of European corn borer. Its larvae grow and pupate in the eggs, preventing borer hatch. Start release when ECB flight begins. In sweet corn, release at 30 to 60k per acre per week, for 2 to 3 weeks per block. In pepper, release 90 to 120k per acre per week over 4 weeks. Reproduces in season but does not overwinter. Available from IPM Laboratories, Locke, NY.

Trichogramma pretiosum No common name Caterpillar eggs May be used in Brassica crops and other crops with caterpillar pests.

 

Table 23: Biorational and Organic Disease Control Materials

 The products in this table are botanical, mineral, and synthetic biorational pesticides labeled for disease control in vegetable crops. The symbol OG indicates a product is listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production. 

Active Ingredient and Trade Name Target Pests Labeled Crops Comments/material type
Acibenzolar-S-methyl (Actigard 50 WG) Downy mildews, bacterial diseases, rusts Crucifers, tomato, spinach Synthetic, Plant defense activator.
Cottonseed Oil, Corn Oil, Garlic Oil (Mildew CureOG) Powdery mildew Most crops Botanical

Copper sulfate (Basic Copper 53OG)

Many bacterial and fungal diseases

Most crops

Mineral

Copper hydroxide (Champ WGOG) Bacterial blight, black rot (Xanthomonas), downy mildew, powdery mildew, Anthracnose, Phompsis, late blight, Botrytis, leaf spots Most crops Mineral
Cuprous oxide (Nordox 75 WGOG) Bacterial blight, black rot (Xanthomonas), downy mildew, powdery mildew, Anthracnose, Phomopsis, late blight, Botrytis, leaf spots Most crops Mineral
Hydrogen dioxide  (OxiDate 2.0OG) Alternaria, Phytophthora, Pythium, Rhizoctonia, Fusarium Wilt, Sclerotinia, Anthracnose, bacterial blight, Botrytis, powdery mildew, rust Beans, cucurbits, celery, crucifers, leafy vegetables tomato, pepper, onions, potato, herbs, root crops Synthetic. Contact activity only
Kaolin (Surround WPOG) Powdery mildew, sunburn and heat stress. All crops Mineral.
Neem Oil (TrilogyOG, Triact 70OG) Anthracnose, Botrytis, downy mildew, powdery mildew, scabs, rusts, leaf spots and blights Most crops Botanical

Oils, Petroleum based (JMS Stylet-OilOG, CivitasOG,& Suffoil-XOG)

Alternaria, Gummy Stem blight, Powdery mildew, Rust

Most crops

Synthetic and natural oils

Potassium Bicarbonate (KaligreenOG, MilStopOG) Alternaria, Anthracnose, Botrytis, downy mildew, Fusarium, Leaf spots, Phytophthora, powdery mildew Beans, crucifers, cucurbits, eggplant, lettuce, peppers, potato, tomato, spinach, wheat Synthetic, Biopesticide, Armicarb 100 is not OMRI listed, but MilStop and Kaligreen are.
Potassium Phosphite (Helena ProPhyt) Downy mildews, Phytophthora species, Pythium species Cucurbits, crucifers, onion, potato, tomato, lettuce, spinach Mineral, Systemic. Drench at transplant.
Mono- and dibasic sodium, potassium, and ammonium phosphites (Phostrol) Downy mildews, Phytophthora species, Pythium species Most crops Synthetic, Use caution when using in a tank mix
Monopotassium phosphate (Nutrol) Powdery Mildew Cucurbits, peppers, and tomatoes Synthetic, Can be used in greenhouse on some crops

Potassium silicate (Sil-MATRIX)

Powdery Mildew, Leaf spots

Most crops

Mineral, Broad spectrum preventive fungicide

Reynoutria sachaliensis Extract (RegaliaOG)

Powdery Mildew, Botrytis,  Leaf spots, Bacterial spot, speck, and canker

Cucurbits, peppers, lettuce, tomato, strawberry, grapes

Botanical, Plant defense activator. Use caution in tank mix.OMRI listed.

Rosemary and Clove Oils (Phyta-Guard EC) Powdery Mildews, bacterial spot Most crops Botanical

Rosemary, Clove, and Thyme Oils (Sporan EC)

Bacterial Spot, Early Blight, Gray Mold, Late Blight, Powdery mildew, Downy mildew

Most crops

Botanical

Rosemary, Thyme, and Clove Oil (SporatecOG) Anthracnose, Botrytis, downy mildew, powdery mildew, leaf spots, rusts, bacterial spot Most crops Botanical

Streptomycin Sulfate (Agri-Mycin 17)

Bacterial diseases Celery, peppers, tomato, potato Biological anti-biotic

Sesame Oil (OrganocideOG)

Powdery Mildew, Leaf spots

Most crops

Botanical
Sulfur (Micro SulfOG, Microthiol DisperssOG, Kumulus DFOG) Powdery mildew, leaf spots Most crops Mineral

 

Table 24: Microbial Disease Control Products

The materials listed in this table are formulated from living microorganisms and/or their byproducts. The symbol OG  indicates a product is listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production. 

Trade name Active ingredient Target Diseases Labeled crops Comments
Actinovate AGOG Streptomyces lydicus Downy mildew, powdery mildew, Botrytis, Sclerotinia spp., Pythium, Phytophthora, Fusarium, Rhizoctonia Greenhouse use only for vegetable crops Seed and soil treatment (drench/in-furrow), greenhouse foliar sprays
Bio-Save 10 LPOG Pseudomonas syringae Strain ESC-10 Fusarium and Helminthosporium storage rots Potato Post-harvest application
Bio-TamOG

Trichoderma asperellum & Trichoderma gamsii

 Fusarium. Rhizoctonia, Pythium, Phytophthora, Sclerotinia, Sclerotium, Verticillium Corn, cole crops, fruiting vegetables, cucurbits, leafy vegetables, legumes, root, tuber, and corm vegetables, herbs, onions

Soil treatment

 

Companion Liquid (& WP) Biological FungicideOG

Bacillus subtilis GB03

Anthracnose, Botrytis, bacterial diseases,  Powdery mildew, Phytophthora, Pythium, Rhizoctonia, Leaf spots

All crops

Soil treatment, hydroponics, seed treatment

CeaseOG

Bacillus subtilis QST 713 strain

Rhizoctonia, Pythium, Phytophthora, Fusarium

Most crops

Soil drench

OMRI listed, greenhouse use

 

Contans WGOG Coniothyrium minitans Strain CON/M/91-08 Sclerotinia sclerotiorum
Sclerotinia minor
Most crops (Bayer formula NOT labeled for tomato) Soil treatment
 
DiTera DFOG Myrothecium verrucaria Strain AARC-0255 Nematodes Celery, lettuce, spinach, crucifers  
Double NickelOG Bacillus amyloliquefaciens Botrytis, Alternaria, fungal leaf spots & blights, powdery mildew, downy mildew, soilborne pathogens: Rhizoctonia, Pythium, Fusarium, Sclerotinia, (suppression only: rust, late blight, early blight),
 
Cucurbits, fruiting and leafy vegetables, brassicas, asparagus, bulbs, legumes/beans, sweet corn & popcorn, herbs  
MycostopOG Streptomyces griseoviridis Strain K61 Fusarium, Alternaria, Phomopsis, Botrytis, Pythium, Phytophthora, Rhizoctonia Beans, lettuce, carrots, crucifers, onions, spinach, tomato, root crops, herbs Seed or soil treatment
 
ObtegoOG

Trichoderma asperellum ICC 012

Trichoderma gamsii ICC 080

Fusarium, Phytophthora, Pythium, Rhizoctonia, Sclerotinia Cucurbits, leafy vegetables, fruiting vegetables, herbs  

Prestop WPOG

PVentOG

Gliocladium catenulatum Strain Ji1446

Pythium, Phytophthora, Rhizoctonia, Fusarium, Verticillium, Botrytis

Most crops. See label for crops registered for incorporated or drench treatment only.

 

RhapsodyOG Bacillus subtilis QST 713 Alternaria, bacterial blight(Xanthomonas), downy mildew, powdery mildew, Sclerotinia spp., Botrytis, rust, Pytophthora infestans Broccoli, carrot, lettuce, onion, pepper, tomato, herbs

Greenhouse Use.

RootShieldOG Trichoderma harzianum Rifai Strain KRL-AG2 Pythium, Rhizoctonia, Fusarium, Cylindrocladium, Thielaviopsis Eggplant, pepper, tomato, lettuce, crucifers, cucurbits, herbs, bulb crops

In-furrow treatment, greenhouse use

RootShield PlusOG Trichoderma harzianum Rifai Strain T-22 & T. viriens Strain G-41 Pythium, Rhizoctonia, Fusarium, Cylindrocladium, Thielaviopsis Eggplant, pepper, tomato, lettuce, crucifers, cucurbits, herbs, bulb crops soilborne diseases, greenhouse use

Serenade OptiOG, Serenade ASOOG

Bacillus subtilis QST 713 Alternaria, Anthracnose, Botrytis, downy mildew, powdery mildew, rust, Helminthosporium diseases, Didymella, Phoma, Bacterial diseases Most crops

Can also be used for postharvest disease protection

SonataOG Bacillus pumilis QST 2808 Alternaria, Downy mildew, Powdery mildew, Rust Most crops  
StargusOG Bacillus amyloliquefaciens F727 Fusarium, Phytophthora, Pythium, Rhizoctonia, Sclerotinia, downy mildew, Botrytis Most crops  
Subtilex NG Bacillus subtilis MBI 600 Rhizoctonia, Fusarium, Pythium, Powdery mildew Pepper, tomato, eggplant, cucurbits For greenhouse use only.

Taegro 2OG

Bacillus amyloliquefaciens FZB24 Rhizoctonia, Fusarium, Sclerotinia, Pythium, Phytophthora, leaf spots, Powdery mildew Fruiting vegetables, cucurbits, leafy vegetables In-furrow, transplant drench, basal spray for primarily soilborne diseases. 
Triathlon BAOG Bacillus amyloliquefaciens D747 Botrytis, Rhizoctonia, Fusarium, Sclerotinia, Pythium, Phytophthora, leaf spots, powdery mildew, downy mildew Most crops  

  

Disease Management

 

Plant diseases can result from a combination of many factors. Under certain conditions, viruses, nematodes, bacteria, fungi, heat, cold, chemicals and air pollution can all cause plant disease. By creating conditions that promote plant vigor, losses due to disease can be minimized.

  • When diseases begin early in the season, yield and quality are more likely to be reduced. Always use disease-free seed, transplants, or cuttings.
  • Use hot water and/or fungicide-treated seed where appropriate. Hot water treatment may prime the seeds to sprout; treatment should be done as close to planting as possible.
  • Pasteurize seedbed soil and potting soils with steam or chemicals. Unopened bags of soilless media do not have to be treated.
  • Disinfect pots, flats, tools and greenhouse surfaces before planting.
  • Avoid the reintroduction of disease-causing organisms to disinfected soil.
  • Do not let pathogens get a head start by practicing good sanitation. Destroy plant debris, trash piles, and weeds that harbor pathogens. Remove and destroy infected plants and plant parts when feasible. Practice crop rotation.
  • Promote plant vigor. Do not overwater or plant in poorly drained soils. Use fertilizers, growth regulators, herbicides, insecticides, and fungicides only as directed. Measure them accurately and apply them properly to avoid toxicity to the plants and to yourself.
  • Some healthy plants can succumb to disease. Select varieties that are resistant to the diseases that you know are a problem in your area.
  • Purchase plants from a reputable source and protect plants from pathogens by following a suitable spray program. Knowing the diseases of your crop and the most effective time to begin spraying can save a crop and your money.
  • Air-blast sprayers can increase the spread of bacterial diseases.
  • Effective control of plant diseases depends upon the accurate identification of the disease. Contact your regional or state Extension specialist or plant disease clinic (see Specimens for Disease Diagnosis below).

Hot Water Treatment of Seed

Ideally, seed should be custom treated by request. If this is not possible, seed can be hot-water treated at home. Some lots of seed can be vulnerable to heat treatment. Always treat a small amount of seed (50-100) of each lot before treating the remainder of the lot. After the test treatment, air dry completely and then moisten for a germination test. Include untreated seed of the same lot for comparison. Treated seed should be used in the current season. Small seeded crops such as brassicas, carrot, pepper, etc. are the most appropriate for hot water treatment. Each seed type has a corresponding temperature and length of time for treatment.  Full instructions for treating seed on your own may be found here: https://ag.umass.edu/vegetable/fact-sheets/hot-water-seed-treatment. Always check with the seed source to make sure it has not already been treated.

Specimens for Disease Diagnosis

Effective control of plant disease depends upon the accurate identification of the cause. Accurate and rapid diagnosis of a plant disease by diagnostic labs requires examination of specimens that are representative of the disease, plus a review of information concerning the growing of the crop. The diagnosis and recommendations reported to grower are based on this information. Plants in advanced stages of decay or desiccation, or those that arrive with no case history information, cannot be diagnosed properly. Before sending the specimen, contact your regional or state Extension specialist or plant disease clinic. Deliver the specimen by overnight mail. Some states may charge a fee for diagnostic services. Supply as much of the following information as possible:

  • Your name, address, zip code, phone number and e-mail address.
  • Crop, cultivar, and date collected.
  • Planting size (acres) or number of plants.
  • Percentage of plants diseased.
  • Distribution of disease (general or all over field, scattered here and there, or localized in a small area of field).
  • Symptoms you are concerned about (blight, wilt, stunting, death, yellowing, leaf mottle, stem rot, root rot, fruit rot, leaf spot, die back, etc.).
  • Chemicals applied, including dates and rates of fertilizers, fungicides, nematicides, herbicides, and growth regulators.
  • Any information that you believe may be important about the circumstances leading to the disease.

Virus Diseases

Many different viruses can infect vegetable crops. Some, like Papaya Ringspot Virus-W, have a narrow host range, while others, like Cucumber Mosaic Virus and Tomato Spotted Wilt Virus, infect a wide variety of vegetable crops as well as ornamentals and weeds. Symptoms of viral infection are most evident on foliage and fruit. However, the symptoms are not always unique to viruses and may closely resemble nutritional disorders, herbicide injury, or insect feeding. A subtle but common symptom of viral infection is overall stunting and reduction in yield.

Viruses are spread in a variety of ways. Mechanical transmission through handling of plants or use of contaminated tools is an efficient means of spreading Tobacco Mosaic Virus and Potato Virus X. Most viruses, however, are not spread in this manner. Insects such as aphids, thrips, mites, leafhoppers, and beetles provide the most important means for viruses to move from infected to healthy plants. Some viruses, such as Tomato Ringspot Virus and Squash Mosaic Virus, can be transmitted through infected seed. Perennial weeds and ornamental hosts provide an important reservoir for viruses to survive from one season to the next.

Aphids are the most important primary and secondary vectors of viral diseases. Depending on their relationship with the aphid, viruses are classified as either persistent or non-persistent. Intermediate forms also exist. Aphids that acquire persistent viruses do so after a minimum feeding time of 10-60 minutes. Following acquisition, a latency period of at least 12 hours must pass before the aphid can transmit the virus. The aphid remains infectious for at least a week, or in some cases, for its entire life. With non-persistent viruses, the aphid can pick up the virus rapidly (within seconds or minutes) while probing the host tissue and can transmit the virus immediately to another plant. However, the ability of the aphid to successfully transmit the virus is quickly lost (within minutes). Insecticides increase the spread of non-persistent viruses by stimulating probing activity of the aphid. Contact insecticides are generally less useful than systemics for controlling insect-vectored viruses.

In general, the spread of viruses is best controlled by cultural practices such as cultivar selection, planting date and location, weed reduction, and roguing of diseased plants. Row covers may prevent aphids from probing and feeding on plants early in the season, preventing the spread of viruses. Occasionally, seed or transplants are infected and the problem is not apparent until well into the growing season. There are no chemical control measures for virus diseases other than those directed at the vector or weed hosts. For more specific control measures, refer to the crop.

Fungicides and Bactericides

Fungicides and bactericides are used to prevent, not cure diseases. Applications initiated before disease appears or at the first sign of disease, are the most effective way to use these pesticides. Knowledge of the cause of the disease is required to select the proper material. Your regional and state specialist can assist you in determining the cause (see Disease Diagnosis above). Note that the continuous use of certain bactericides or fungicides can result in pathogens becoming resistant to these chemicals.

For detailed information about fungicides and bactericides, see Table 23, 24, and 25 on pages 79, 80, and 84 respectively.

Resistance Management

Pathogens that survive an application of a fungicide are likely to pass the trait that enabled them to survive on to their offspring. A single genetic change in the pathogen can render single-site mode of action (systemic) fungicides ineffective. Repeated applications of the same type of fungicide exert selection pressure on the pathogen population and eventually eliminate almost all the susceptible individuals from a pest population.  Resistance can develop in a very short time.

It is necessary to practice resistance management to preserve the useful life of a fungicide. The most effective way to extend the useful life of a product is to use it once and then alternate with a fungicide with a different mode of action. Fungicides are grouped according to chemical class or site of their activity and assigned a group number by the Fungicide Resistance Action Committee (FRAC Group). To select fungicides with different modes of action, see resistance group (FRAC) in Table 25 (page 84) and in the following section Fungicides and Bactericides Alphabetical Listing by Trade Name. Fungicides that are systemic (penetrant) have a single site of action upon the target organisms' physiology and are particularly prone to developing resistance. Use systemic fungicides with a single site of action once per season. Use the most effective chemical against a particular pest first. Do not apply fungicides with a high risk of resistance development (systemic, single mode of action such as Group 11 strobilurins) when disease is severe as this situation results in high selection pressure upon the pathogen.

There are many other techniques that can help delay the onset of resistance. Many resistance management techniques help minimize the use of pesticides so a lower proportion of each pest generation is exposed to the toxin.

  • Integrate chemical controls with effective cultural, mechanical, physical, and genetic management options.
  • Scout, monitor, and use action thresholds to determine if fungicide applications are necessary.
  • Good spray coverage helps do the job right the first time and avoids unnecessary repeat applications: use the proper size nozzles at the correct angle or orientation and an adequate amount of water per acre.
  • Tank mixes of systemic materials with contact fungicides help delay the onset of resistance to the systemic fungicides. Most contact fungicides have a multi-site mode of action (FRAC Group M plus a number).

NOTE: There is no relationship between insecticide groups, herbicide groups, and fungicide groups. For example, there is no problem using a Group 1 herbicide and a Group 1 insecticide or fungicide.

Toxicity of Fungicides

All pesticides are poisonous. However, some are more toxic than others. The toxicity of the pesticide is usually stated in the precaution on the label. For example, a skull and crossbones figure and the signal word "Danger" are always found on the label of highly toxic (Toxicity Class I) materials. Those of medium toxicity (Toxicity Class II) carry the signal word "Warning." The least toxic materials (Toxicity Class III) have the signal word "Caution." The toxicity of a pesticide is expressed in terms of oral and dermal LD50. LD50 is the dosage of poison that kills 50% of test animals (usually rats or rabbits) with a single application of the pure pesticide for a given weight of the animal (mg/kg of body weight). The lower the LD50 value, the more toxic the material. Oral LD50 is the measure of the toxicity of pure pesticide when administered internally to test animals. Dermal LD50 is the measure of the toxicity of pure pesticide applied to the skin of test animals. Generally, an oral application is more toxic than a dermal one.

Table 25: Information about Fungicides and Bactericides

Active Ingredient

Signal Wordz

Trade Name

Resistance Group (FRACy code)

Dermal LD50 mg/kg Oral LD50 mg/kg
ametoctradin & dimethomorph C Zampro 45 & 40 >5,000 >500 <2,000
azoxystrobin

C

Quadris, Dynasty 11 >2,000 - 4,000 >2,000 - 5,000

azoxystrobin & chlorothalonil

W

Quadris Opti

11 & M5

>5,000

1,750

azoxystrobin & difenoconazole C Quadris Top 11 & 3 >2,000 >2,000
azoxystrobin & flutriafol C Topguard EQ 11 & 3 >5,000 >5,000
azoxystrobin & mefenoxam C Ridomil Gold SL 11 & 4 >4,000 >5,000

azoxystrobin & propiconazole

W

Quilt, Quilt Xcel, Trivapro B

11 & 3

>5,000

1,750 / 1030

azoxystrobin & tebuconazole W Custodia 11 & 3 >2,000 >300
benzovindiflupyr D Trivapro A 7 >5,000 550
benzovindiflupyr & difenoconazole W Aprovia Top 3 & 7 >5,000 1,750
benzovindiflupyr & azoxystrobin & propiconazole W Trivapro 7 & 11 & 3 >2,000 550

boscalid

W

Endura

7

>2,000

>2,000
chlorine

 D

Agclor 310 NC >20,000 8,910
chlorothalonil

C ,W

Bravo Weather Stik, Bravo Ultrex, Bravo Zn, Echo 720, Echo 90 DF, Equus 720 SST, Initiate 720, Initiate Zn, Orondis Opti B M5 >2,000 -10,000 >3,750 -10,000
chlorothalonil & cymoxanil C Ariston M5 & 27 >5,050 >5,000
chlorothalonil & oxathiapiprolin D Orondis Opti M5 & 49 >2,000 >5,000
Coniothyrium minitans C ContansOG BM2 >2,500 >2,500
copper hydroxide C, D Champ WGOG, Champ Dry Prill, Champ Formula 2 Flowable, KalmorOG, Kocide 2000, Kocide 2000-OOG, Kocide 3000, Kocide 3000-OOG, ChampION++OG, Nu-Cop (50DFOG, 50WPOG, HBOG), Kentan DF M1 1,300->5,000 489-1,847
copper hydroxide & copper oxychloride  W Badge X2 OG M1 >2,000 >300
cuprous oxide C Nordox 75 WGOG M1 >2,000 3,165
copper octanoate C Camelot O, Cueva M1 >2,000 >2,000
copper oxychloride and copper hydroxide C, W Badge SC, Badge X2 M1 >300 >2,000
copper sulfate (basic copper) C, W, D Basic Copper 53OG, Cuprofix Ultra, Cuproxat FLOG, Cuproxat, Phyton 35, MasterCopOG M1 >2,000-8000 1,000-2,521

cyazofamid

C

Ranman, Ranman 400 SC

21

>2,000

>5,000

cyflufenamid C Torino U6 >2,000 <,2,000
cymoxanil

W

Curzate 60 DF 27 >2,000 >433

cyprodinil & fludioxonil 

C

Switch 62.5

9 & 12

>2,000

>5,000

difenoconazole & cyprodinil

C

Inspire Super

3 & 9

>5,000

5,000

dimethomorph

C

Forum 15 >2,000 >5,000

famoxadone & cymoxanil 

C

Tanos

11 & 27

>2,000

>5,000

fenamidone

C

Reason 500 SC

11

>5,000

>5,000

fenhexamid

C

Decree 50 WDG

17

>2,000

>2,000

fluazinam

W

Omega 500F, Omega TopMP

29

>2,000

>5,000

fludioxonil

C

Maxim4FS, Maxim PSP, Cannonball WG, Emblem 12 >2,020 1,971
fludioxonil & mancozeb C Maxim MZ 12 & M3 >5,000 >5,000

fluopicolide

C

Presidio

43

>4,000

>2,000

fluopyram C Velum Prime 7 >2,000 >2,000
fluopyram & pyrimethanil C Luna Tranquility 7 & 9 >2,000 >2,000
fluopyram & tebuconazole C Luna Experience 7 & 3 >2,000 >2,000
fluopyram & trifloxystrobin C Luna Sensation 7 & 11 >2,000 >2,000
flutolanil C Moncut 70 DF 7 >5,000 >5,000
flutolanil & mancozeb C Moncoat MZ 7 & M3 >5,000 >5,000
flutriafol C Topguard Fungicide, Rhyme 3 >2,000->5,000 >2,000
fluxapyroxad & pyraclostrobin C Priaxor, Merivon 7 & 11 >5,000 >300-<2,000
fosetyl aluminum

C

Aliette WDG 33 2,000 >5,050
hydrogen peroxide & peroxyacetic acid D Oxidate 2.0OG, ZeroTol 2.0OG NC 1,040 3,622
iprodione

C

Iprodione 4L AG, Rovral 4F, Nevado 4F 2 1,170 - 2,000 2,000 - 2,860
mancozeb

C

Penncozeb (75DF, 80WP), Manzate (Max, Pro-Stick), Dithane (M-45, F-45 Rainshield), Potato Seed Treater (6%, PS), Roper (DF, DF Rainshield) M3 >2,000 >5,000

mancozeb & copper 

D

ManKocide

M3 & M1

>5,000

2,535

mandipropamid 

C

Revus, Micora, Orondis Ultra B

40

>5,000

>5,000

mandipropamid & difenoconazole

C

Revus Top

3 & 40

>5,000

2,958

mefenoxam C Ridomil Gold (GR, SL), Apron XL, Ultra Flourish 4 2,020 1,172
mefenoxam & chlorothalonil

W

Ridomil Gold Bravo SC 4 & M5 >2,020 1,172
mefenoxam & copper 

D

Ridomil Gold Copper 4 & M1 2,020 560
mefenoxam & mancozeb 

C

Ridomil Gold MZ WG 4 & M3 >2,000 >5,000
metconazole C Quash 3 >5,000 1,750
metrafenone C Vivando U8 >5,000 >5,000
metiram C Polyram 80 DF M3 >2,000 >5,000
myclobutanil

W

Rally 3 >5,000 1,870
oxathiapiprolin C Orondis (Ultra A, Gold 200, Opti A) 49 >5,000 >5,000
oxathiapiprolin & mandipropamid C Orondis Ultra 49 & 40 >5,000 >5,000
PCNB C Blocker (4F, 10G), Terraclor 400 14 >2,020 >5,050
penthiopyrad C Fontelis 7 >5,000 >5,000
phosphorus acid (salts of)

C

Agri-Fos, Alude, Fosphite, KPhite, Phostrol, ProPhyt, Rampart, Reveille 33 >2,000 >5,000
polyoxin D C Oso 5% SC AKA VeggieTurbo 5 SCOG, Ph-D, Affirm WDG 19 >2,000 4,916
potassium bicarbonate C KaligreenOG, MilStopOG NC >5,000 2,700
potasium dihydrogen phosphate C Nutrol NC    
propamocarb

C

Previcur Flex 28 >3,920 2,000-8,550
propiconazole

W

Tilt, PropiMax EC, Bumper (41.8EC & ES) 3 >5,000 1,310

propiconazole & trifloxystrobin

W

Stratego

3 & 11

>5,050

4,757

prothioconazole C Proline 480SC 3 >5,000 >2,000-<5,000
prothioconazole & trifloxystrobin W Stratego YLD 3 & 11 >5,000 >5,000
pydiflumetofen & fludioxonil C Miravis Prime 7 & 12 >5,000 2,968

pyraclostrobin

C, W

Headline, Headline SC, Cabrio EG

11

200 - >2,000

2,000 - 4,000

pyraclostrobin & boscalid 

C

Pristine, Pageant Intrinsic

11 & 7

>2,000

1,490

pyraclostrobin & dimethomorpg C Cabrio Team 11 & 40 >4,000 260

pyraclostrobin & metconazole

W

Headline AMP

11 & 3

>5,000

500

pyraclostrobin & metiram

C

Cabrio Plus

11 & M3

>2,000

> 500-<2,000

pyrimethanil

C

Scala SC

9

>5,000

4,505

quinoxyfen

C

Quintec

13

>2,000

>2,000

streptomycin

C

Agri-Mycin 17 25 >2,000 >5,000

sulfur

C

Microthiol DisperssOG, Kumulus DFOG, Micro SulfOG, Sulfur 6L, Microfine Sulfur

M2

>2,000

>2,000

tebuconazole C Orius 3.6F 3 >2,000 >2,000
tetraconazole C Mettle 125 ME 3 >2,000 >4,090

thiabendazole

C

Mertect 340-F

1

>5,050

>5,000

thiophanate-methyl

C

Topsin M WSB, Topsin 4.5 FL,  Nufarm T-Methyl (70WSB, 4.5F), Incognito (4.5 F, 85 WDG) 1 >2,000 >5,000
triphenyltin hydroxide D Super Tin (80 WP, 4L) 30      500      160
trifloxystrobin

C

Flint Extra, Gem 500 SC 11 >2,000 >5,050

triflumizole

C

Procure 480 SC, Trionic 4SC

3

>5,000

>1,400

thiram

C

42-S Thiram

M3

>4,400

2,950

zoxamide & chlorothalonil C Zing! 22 & M5 >5,000 1,750-5,000
zoxamide & mancozeb

C

Gavel 75 DF 22 & M3 >5,000 >5,000

z Signal Word C = Caution; W = Warning: D = Danger

y FRAC = Fungicide Resistance Action Committee 

The symbol OG   indicates a product is listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production. See Organic Certification section for more details. Note that for a given active ingredient, some products may be OMRI listed while others are not.

Fungicides and Bactericides Alphabetical Listing by Trade Name

The symbol OG   indicates a pesticide that has been listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production. REI = Re-Entry Interval expressed in hours (h). At the time of writing, all products listed were registered in at least one New England state. Check registration status in your state before using any product.

3336 F (thiophanate-methyl): A systemic fungicide with broad spectrum control. Also labeled for greenhouse transplants. REI 12h, Group 1

42-S Thiram (thiram): A seed treatment with a wide host range. REI 24h, Group M3 

Actigard 50 WG (acibenzolar-S-methyl): Plant defense activator used for bacterial diseases and Downy Mildews. REI 12h, Group 21

Actino-IronOG(Streptomyces lydicus WYEC): Biological soil and seed treatment for Fusarium, Rhizoctonia, Pythium, and Phytophthora with added iron. REI 4h, Group NC

Actinovate AG (Streptomyces lydicus): Biological for greenhouse use only in vegetable crops. REI 1h, Group NC

Agclor 310 (sodium hypochlorite): A commercial bleach solution registered for use to control postharvest rots of vegetables. Group NC

Affirm WDG (polyoxin-D): Broad-spectrum fungicide for foliar and soilborne diseases. May be used in greenhouse. REI 4h, Group 19

Agri-Fos (phosphorus acid): A fungicide active against Pythium, Phytophthora, and downy mildew. REI 4h, Group 33

Agri-mycin 17 (streptomycin sulfate): A bactericide. REI 12h, Group 25

Aliette WDG (fosetyl Al): A fungicide active against Pythium, Phytophthora, and  downy mildew. REI 12h, Group 33

Alude (phosphorous acid): A fungicide active against Pythium, Phytophthora, and downy mildews labeled for greenhouse transplant production. REI 4h, Group 33

Apron XL (mefenoxam): A seed treatment against Pythium and Phytophthora seed rot and damping-off and systemic downy mildews of certain crops. REI 48h, Group 4

Aprovia Top (benzovindiflupyr + difenoconazole): For many diseases of cucurbits, legumes, peppers, tomatoes, sweet potato. REI 12h, Groups 3 & 7

Ariston (chlorothalonil + cymoxanil): Labeled for several diseases on several crops. REI 12h (see label), Groups M5 & 27

BadgeX2OG SC  (copper oxychloride + copper hydroxide): A bactericide and fungicide. REI 24h, Group M1

Basic Copper 53OG (basic copper sulfate): A broad spectrum fungicide. REI 48h, Group M1

Bio-Save 10 LPOG (Pseudomonas syringae ESC-10): Post harvest decay of potato. Group NC

Bio-TamOG (Trichoderma aperellum, T. gamsii): Biological soil treatment for most crops. REI 4h Group BM02

Blocker 4F (PCNB): Soil-borne diseases of brassicas, beans and peas, garlic, tomatoes, and pepper. REI 12h, Group 14

BotryStopOG (Ulocladium oudemansii U3 Strain): A biological control for Botrytis and Sclerotinia diseases. REI 4h, Group NC

Bumper (propiconazole):  Diseases of corn, celery, carrot, chard and bulb crops. REI 12h, Group 3

Bravo (Weather Stik, Ultrex, ZN) (chlorothalonil): A broad spectrum fungicide. REI 12h, Group M5

Cabrio EG (pyraclostrobin): A broad spectrum fungicide for bulb, cucurbit, fruiting, and root vegetables. REI 12h, Group 11

Cabrio Plus (pyraclostrobin + metiram): For management of certin diseases of potato. REI 24h, Groups 11 & M3

Camelot OOG (copper soap): Copper product labeled for greenhouse use on vegetable transplants. REI 4h, Group M1

Cannonball WG (fludioxonil): For management of Sclerotinia, Botrytis and other pathogens on onions and beans. REI 12h, Group 12

Catamaran (potassium phosphite + chlorothalonil): Broad spectrum fungicide and plant activator. REI 12h, Groups 33 & M5

CeaseOG (Bacillus subtilis QST 713): Biological protectant fungicide. REI 4h, Group 44

Champ WGOG (copper hydroxide): Copper fungicide. REI 48h, Group M1

Champ Dry Prill (copper hydroxide):  Copper fungicide. REI 24/48h, Group M1

Champ Formula 2 Flowable (copper hydroxide): Copper fungicide. REI 48h, Group M1

ChampION++ (copper hydroxide): Copper fungicide. REI 48h, Group M1

CompanionOG (Liquid, WP) (Bacillus subtilis strain GB03): Biological fungicide. REI 4h, Group 44

Contans WG OG (Coniothyrium minitans): For Sclerotinia sclerotiorum and Sclerotinia minor diseases. (Bayer fomula not labeled for tomato). Group NC

Cuprofix Ultra 40 Disperss (basic copper sulfate): A broad spectrum fungicide. REI 48h, Group M1

Cuproxat, Cuproxat FLOG (basic copper sulfate): A broad spectrum fungicide. REI 48h, Group M1

Curzate 60 DF (cymoxanil): For late blight of potato and tomato and downy mildew of cucurbits and lettuce. REI 12h, Group 27

Custodia (azoxystrobin + tebuconazole): A broad spectrum fungicide labeled for foliar diseases of corn. REI 12h (for corn), Groups 3 & 11

DiTera DFOG (Myrothecium verrucaria Strain AARC-0255): For managment of plant parasitic nematodes. REI 4h, Group NC

Dithane (M-45, F-45 Rainshield) (mancozeb): A broad spectrum, protectant fungicide. REI 24h, Group M3

Decree 80 WDG (fenhexamid): Botrytis control in greenhouse transplants. REI 12h, Group 17

Double NickelOG 55 and LC (Bacillus amyloliquefaciens): Microbial fungicide. REI 4h, Group 44

Dynasty (azoxystrobin): A broad spectrum seed treatment fungicide for diseases of seed-borne diseases. REI 4h, Group 11

Echo (90DF, 720) (chlorothalonil): A broad spectrum fungicide. REI 12h, Group M5

EcoSwingOG (extract of Swinglea glutinosa): Preventive biological fungicide for Alternaria leaf spot, Botrytis, and powdery mildew on many crops. Also labeled for greenhouse use. Activates ISR (induced systemic resistance). REI 12h, Group NC

Emblem (fludioxonil): For greenhouse use only on plants and transplants of listed crops. REI 12h, Group 12

Endura (boscalid): A protectant fungicide for legumes, brassicas, bulb vegetables, fruiting vegetables, lettuce, and root and tuber vegetables. REI 12h, Group 7

Equus 720 SST (chlorothalonil): A broad spectrum fungicide. REI 12h, Group M5

Flint (trifloxystrobin): A strobilurin fungicide with broad-spectrum activity. REI 12h, Group 11

Fontelis (penthiopyrad): A fungicide with broad host clearance for leaf spots, blights, anthracnose, and Sclerotinia diseases. REI 12h, Group 7

Forum (dimethomorph): A fungicide for use against Phytophthora and downy mildew of bulb, cucurbit and fruiting vegetables, lettuce, potatoes, and tomatoes. REI 12h, Group 40

Fosphite (phosphorus acid): A phosphorous acid fungicide active against Pythium, Phytophthora, and downy mildew. REI 4h, Group 33

Gavel (75 DS, DF) (zoxamide + mancozeb): A broad-spectrum protectant fungicide for disease control in potatoes, cucurbits, and tomatoes. REI 48h, Groups 22 & M5

GEM 500 SC (trifloxystrobin): Broad spectrum fungicide. REI 12h, Group 11

Headline, Headline SC (pyraclostrobin): A broad spectrum strobilurin fungicide for use in legumes, corn, tuberous, and corm vegetables. REI 12h, Group 11

Headline AMP (pyraclostrobin + metconazole): For diseases of corn. REI 48h, Groups 11 & 3

Heritage (azoxystrobin): Preventative and curative broad-spectrum fungicide. See supplemental label for use on vegetable transplants grown in the greenhouse. REI 4h, Group 11

Incognito (4.5 F, 85 WDG) (thiophanate-methyl): A systemic fungicide with broad spectrum control. REI (Varies with crop, see label) Group 1

Initiate (720, ZN) (chlorothalonil): A broad spectrum fungicide. REI 12h, Group M5

Inspire Super (difenoconazole + cyprodinil):  For powdery mildew. REI 12h, Groups 7 & 9

Iprodione 4L AG (Iprodione): For Alternaria, Botrytis and Rhizoctonia diseases; sclerotinia diseases; in beans, broccoli, carrots, dry bulb onions, and lettuce; white rot of garlic, . REI 24h, Group 2

JMS Stylet-OilOG, JMS Stylet-Oil (paraffinic oil): Fungal diseases and aphid transmitted viruses. Also labeled for greenhouse use. REI 4h, Group NC

KaligreenOG (potassium bicarbonate): Powdery mildew and other foliar diseases. REI 4h, Group NC

KalmorOG (copper hydroxide): Broad spectrum bactericide and fungicide. REI 48h, Group M1

Kentan DF (copper hydroxide): Broad spectrum bactericide and fungicide. REI 48h, Group M1

K-Phite 7LP (phosphorus acid): Pythium, Phytophthora, and downy mildew; also labeled for greenhouse transplant production.  REI 4h, Group 33

Kocide 2000, Kocide 2000-OOG, Kocide 3000, Kocide 3000-OOG (copper hydroxide):  Broad spectrum bactericide and fungicide. REI 48h, Group M1

Kumulus DFOG (sulfur): Broad spectrum fungicide, particularly for powder mildew. REI 24h, Group M2

Luna Experience (fluopyram + tebuconazole):  Fungal diseases on watermelon only. REI 12h, Groups 3 & 7

Luna Sensation (fluopyram + trifloxystrobin): Foliar and soilborne diseases of several crops. REI 12h, Groups 7 & 11

Luna Tranquility (fluopyram + pyrimethanil): For fungal diseases of potato. REI 12h, Groups 7 & 9

ManKocide (copper + mancozeb): A broad spectrum fungicide and bactericide. REI 48h, Groups M3 & M1

Manzate (Max, Pro-Stick) (mancozeb): A broad spectrum fungicide. REI 24h, Group M3

MasterCop (copper sulfate pehtahydrate): A broad spectrum fungicide and bactericide. REI 48h, Group M1

Maxim 4FS (fludioxonil): A seed treatment fungicide for seed-borne and soil-borne fungi of several vegetable crops. REI 12h, Group 12

Maxim MZ (fludioxonil + mancozeb): A seed treatment fungicide for certain diseases of potato. REI 12h, Group 12

Maxim PSP (fludioxonil): A seed treatment fungicide for certain diseases of potato. REI 12h, Group 12

Merivon (fluaxapoxad + pyraclostrobin): For fungal diseases including powdery mildew. REI 12h, Groups 7 & 11

Mertect 340-F (thiabendazole ): A seed treatment for fungal seed-borne and soil-borne diseases. REI 12h, Group 1

Micora (mandipropamid): Oomycete fungicide labeled for greenhouse use. REI 4h, Group 40

Microthiol DisperssOG (sulfur): A protectant fungicide particularly useful for powdery mildew. May be used in greenhouse. REI 24h, Group M2

Microfine Sulfur (sulfur): A protectant fungicide particularly useful for powdery mildew. REI 24h, Group M2

Micro SulfOG (sulfur): A protectant fungicide particularly useful for powdery mildew. May be used in greenhouse. REI 24h, Group M2

Mildew CureOG (cottonseed, corn, and garlic oils): For powdery mildew. Group NC

MilStopOG (potassium bicarbonate): Powdery mildew and other foliar diseases of greenhouse crops. REI 1h, Group NC

M-PedeOG (insecticidal soap): Insecticide/fungicide labeled for greenhouse use. REI 12h

Moncoat MZ (flutolanil + mancozeb): Potato seed piece treatment for late blight. REI 24h, Groups 7 & M3

Moncut 70 DF (flutolanil): For control of soil-borne fungal diseases of brassicas and potatoes. REI 12h, Group 7

Mural (azoxystrobin & benzovindiflupyr): Broad-spectrum fungicide for foliar applications for greenhouse-grown vegetable transplants grown for resale to consumers - cucurbits, fruiting vegetables, tomatoes. NOT for transplants inteneted for commercial field use. REI 12h, Group 11 and 7

MycoStopOG (Streptomyces griseoviridis K61):  Biological seed or soil treatment. REI 4h, Group NC

Nevado (Iprodione): For Alternaria, Botrytis, Rhizoctonia and Stemphylium diseases; sclerotinia diseases; in beans, broccoli, carrots, crucifers, dry bulb onions, potatoes, and lettuce; white rot of garlic, . REI 24h, Group 2

Nordox 75 WGOG (cuprous oxide): Copper fungicide. REI 12h, Group M1

Nu-Cop (3L, 50DFOG, 50WPOG, HBOG) (copper hydroxide): Copper fungicide. REI 48h, Group M1

Nutrol (potassium dihydrogen phosphate): Protectant fungicide for powdery mildew. REI 4h, Group 33

Nufarm T-Methyl 70WSB, 4.5F (thiophanate-methyl): A systemic fungicide with broad spectrum control. REI (aries with crop, see label), Group 1

ObtegoOG (Trichoderma aperellum, T. gamsii): Biological soil treatment for most crops. REI 4h, Group BM02

Omega 500 (fluazinam): Phytophthora disease, downy mildew, leaf spots, Sclerotina and Sclerotium diseases; late blight and white mold of potatoes. REI 48h, Group 29

Omega Top MP (fluazinam): Late blight and white mold of potatoes. REI 12h, Group 29

OrganocideOG (sesame oil): Powdery mildew. Group NC

Orius (3.6F) (tebuconazole): For onion diseases, and rusts, Powdery mildew, and other fungal diseases of select crops. REI (varies with crop, see label), Group 3

Orondis Opti (chlorothalonil + oxathiapiprolin): Diseases of cucurbits and fruiting vegetables. REI 12h, Groups M5 & 49

Orondis Opti B (chlorothalonil): A broad spectrum fungicide. REI 12h, Group M5

Orondis (Ultra A, Gold 200, Opti A) (oxathiapiprolin): Phytophthora diseases and downy mildew in several crops. REI 4h, Group 49

Orondis Ultra (oxathiapiprolin + mandipropamid): Phytophthora diseases and downy mildew in several crops. REI 4h, Groups 49 & 40

Orondis Ultra B (mandipropamid): Phytophthora diseases and downy mildew in several crops. REI 4h, Group 4

OSO 5% SC (polyoxin D): Broad spetrum fungicide for foliar and soilborne diseases. REI 4h, Group 19

OxiDate 2.0OG (hydrogen dioxide + peroxyacetic acid): Preventive bioicide. REI 0-1h (see label), Group NC

OxiPhos (phosphorus acid + hydrogen peroxide): Preventive bioicide. REI 4h, Groups 33 & NC

Pageant Intrinsic (pyraclostrobin + boscalid): For diseases of greenhouse-grown cucurbits, fruiting vegetables, and leafy greens; and cucurbit, fruiting vegetable, and leafy green transplants for the home consumer market only (NOT for transplants for commercial field production). REI 12h, Groups 7 & 11

Penncozeb (75DF, 80WP) (mancozeb): A broad spectrum fungicide. REI 24h, Groups M3

PhD (polyoxin D): Broad spetrum fungicide for foliar and soilborne diseases. REI 4h, Group 19

Phyton 35 (copper sulfate): Copper sulfate product labeled for greenhouse use on vegetable transplants. REI 48/24h, Group M1

Phostrol (phosphorus acid): A fungicide for Pythium, Phytophthora, and Downy Mildew. REI 4h, Group 33

Polyram 80 DF (metiram): For early and late blight in potatoes. REI 24h, Group M3

Potato Seed Treater 6% (mancozeb): Potato seed piece treatment for Fusarium dry rot. REI 24h, Groups M3

PreFenceOG (Streptomyces griseoviridis K61): Biological seed or soil treatment. REI 4h, Group NC

Presidio 4SC (fluopicolide): A locally systemic fungicide effective against Phytophthora and Downy Mildews of bulb, cucurbit, fruiting, and leafy vegetables. REI 12h, Group 43

PreStopOG (Gliocladium catenulatum J1446): Preventative biological fungicide that can be incorporated into media, applied as a drench or as a foliar spray. REI 4h, Group NC

Previcur Flex (propamocarb): A fungicide for Oomycetes. Previcur should be mixed with Bravo, Maneb or Mancozeb to prevent development of resistance. REI 12h, Group 28

Priaxor (fluxapyroxad + pyraclostrobin): For disease control and in beans, tomato, peas, potato and corn. REI 12h, Group 7 & 11

Pristine (boscalid + pyraclostrobin): For use in bulb vegetables, carrots, cucurbits and celery. REI 12h, Group 7 & 11

PVentOG (Gliocladium catenulatum J1446): Preventative biological fungicide that can be incorporated into media, applied as a drench or as a foliar spray. REI 4h, Group NC.

Procure (triflumizole): Powdery mildew on brassica, cucurbits, and leafy vegetables. REI 24h, Group 3

Proline 480SC (prothioconazole): For diseases of corn, cucurbits, peas, and beans. REI 12h, Group 3

ProPhyte (phosphorus acid): Labeled for Pythium, Phytophthora, downy mildew. REI 4h, Group 33

PropiMax EC (propiconazole): Diseases of Allium species. REI 12h, Group 3

Quadris (azoxystrobin): A strobilurin fungicide with broad spectrum activity. REI 4h, Group 11

Quadris Opti (azoxystrobin + chlorothalonil): Broad spectrum fungicide for dry beans, cucurbit vegetables, potatoes, tomatoes, and onions. REI 12h, Group 11 & M5

Quadris Ridomil Gold (azoxystrobin + mefenoxam): Labeled for potatoes only. REI 0h, Group 11 & 4

Quadris Top (azoxystrobin + difenaconazole): Broad spectrum fungicide. REI 12h, Group 11 & 3

Quash (metraconazole): For managment of several diseases , including white mold, in beans, potato and sweet potato. REI 12h, Group 3

Quilt (azoxystrobin + propiconazole): Broad spectrum fungicide for use in carrots, celery, corn, and bulb crops. REI 12h, Group 11 & 3

Quilt Xcel (azoxystrobin + propiconazole): Broad spectrum fungicide for use in carrots, celery, corn, and bulb crops. REI 12h, Group 11 & 3

Quintec (quinoxyfen): Fungicide for control of powdery mildew in cucurbits. REI 12h, Group 13

Rally 40 SWP (myclobutanil): A fungicide for powdery mildews and rusts of vegetable crops. REI 24h, Group 3

Rampart (phosphorus acid): Labeled for Pythium, Phytophthora, downy mildew. REI 4h, Group 33

Ranman (cyazofamid): Effective against Phytophthora and downy mildew in cucurbits, tomatoes, bulb crops, and potatoes. REI 12h, Group 21

Reason 500 SC (femadione): A fungicide for use against Phytophthora, downy mildew, and white rust on tuberous and corm vegetables, tomatoes, bulb vegetables, lettuce, and cucurbit vegetables. REI 12h, Group 11

RegaliaOG (extract of Reynoutria sachalinensis) : Plant defense activator for fungal and bacterial diseases. REI 4h, Group P5

Reville (phosphorus acid): Labeled for Pythium, Phytophthora, downy mildew. REI 4h, Group 33

Resist (phosphorus acid): Labeled for Pythium, Phytophthora, Fusarium, Rhizoctonia, downy mildew and silver scurf in potatoes. REI 4h, Group 33

Revus (mandipropamid): For use against downy mildew on peppers, brassica, bulb crops, cucurbits, and leafy vegetables. REI 12h, Group 40

Revus Top (mandipropamid + difenoconazole): Broad spectrum fungicide for potatoes and tomatoes. REI 12h, Groups 3 & 40

Rhyme (flutriafol): Labeled for several diseases on several crops.  REI 12h, Group 3

Ridomil Gold (4SL, GR) (mefenoxam): A fungicide active against Pythium, Phytophthora, and the downy mildews. REI 48h, Group 4

Ridomil Gold Bravo SC (mefenoxam + chlorothalonil):  Broad spectrum fungicide containing 4.4% metalaxyl and 72% chlorothalonil effective against both lower and true fungi. REI 48h, Groups 4 & M5

Ridomil Gold MZ 72 (mefenoxam + mancozeb):  Broad spectrum fungicide containing 8% metalaxyl and 64% mancozeb effective against both lower and true fungi. REI 48h, Groups 4 & M3

Ridomil Gold Copper (mefenoxam + copper):  Broad spectrum fungicide containing 4.8% metalaxyl and 60% copper hydroxide effective against both lower and true fungi. REI 48h, Groups 4 & M1

RootShield AG, WPOG (Trichoderma harzianum Rifai strain KRL-AG2):  Biological treatment. REI 0h Group NC

RootShield GranulesOG (Trichoderma harzianum Strain T-22): Biological soil treatment. REI 0h, Group NC

RootShield Plus WP, GranulesOG (Trichoderma harzianum Strain T-22 + T. virens Strain G-41):  Biological fungicide for foliar and soil treatments. REI 0h, Group NC

Roper (DF, DF Rainshield) (mancozeb): A broad spectrum fungicide. REI 24h, Groups M3

Rovral 4 F (iprodione): For Alternaria, Botrytis, Rhizoctonia and Stemphylium diseases; sclerotinia diseases; in broccoli, carrots, dry bulb onions, potatoes; white rot of garlic. REI 24h, Group 2

Scala SC (pyrimethanil): Protective fungicide for bulb, tuberous, and corm vegetables. REI 12h, Group 9

Serenade (ASOOG, OptiOG)  (Bacillus subtilis QST 713): Biological protectant fungicide. REI 4h, Group 44

Sil-MATRIXOG (potassium silicate): Broad spectrum preventive fungicide. REI 4h, Group NC

SonataOG (Bacillus pumilus QST 2808): Biological protectant fungicide. REI 4h, Group NC

Sovran 50 WG (kresoxim-methyl): For powdery mildew and gummy stem blight in cucurbits. REI 4h, Group 11

Spirato (fludioxonil): For greenhouse use only on plants and transplants of listed crops. REI 12h, Group 12

Sporan EC (rosemary, clove, and thyme oils): Contact fungicide with broad crop clearance. Group NC

StargusOG (Bacillus amyloliquefaciens F727): Broad-spectrum preventive biological fungicide for bacterial spot and blights, botrytis blight, late blight, damping off and root rots, downy mildew (depending upon crops, see label). REI 4h, Group 44

Stratego,  Stratego YLD (propiconazole + trifloxystrobin): For diseases of corn. REI 12h, Groups 3 & 11

Subdue MAXX (mefenoxam): For greenhouse-grown transplants for retail sale to consumers. For downy mildew, and soilborne Pythium and Phytophthora diseases of cole crops, curcurbits, fruiting vegetables, leafy vegetables, and bulb crops. (NOT for transplants grown for commercial field use). REI 0/48h, Group 4

Suffoil-XOG (petroleum oils): Fungicide, insecticide, and miticide labeled for greenhouse transplant production. REI 4h, Group NC

Sulfur 6L (sulfur): For powdery mildew on many crops, rust on asparagus, and some mite pests. REI 24h, Group M6

Super Tin 80 WP (triphenyltin hydroxide): For early blight and late blight of potato (restricted use pesticide). REI 48h, Group 30

Switch 62.5 WG (cyprodinil + fludioxonil): A protective fungicide for use in beans, brassica, carrot, herbs, leafy vegetables, and onions. REI 12h, Groups 9 & 12

Taegro 2 (B. subtilis var. amyloliquefaciens FZB24): Biological for soilborne diseases in cucurbits, leafy vegetables, and fruiting vegetables. REI 4h, Group 44

Tanos 50 DF (famoxadone + cymoxanil): A penetrant fungicide with locally systemic and curative activities against Downy Mildew and late blight diseases. REI 12h, Groups 11 & 27

Terraclor 400 (PCNB): A fungicide active against soilborne true fungi labeled for greenhouse transplant production. REI 12h, Group 14

Tilt (propiconazole): A protective fungicide for diseases of beans, beets, carrots, celery, onions, and corn. REI 12h, Group 3

Topguard (flutriafol): Cucurbits, fruiting vegetables. REI (varies with crop, see label), Group 3

Topguard EQ (azoxystrobin + flutriafol): Foliar diseases of brassicas, cucurbits, leafy, and fruiting vegetables. REI 12h, Groups 11 & 3

Topsin (4.5FL, M 70 WSB) (thiophanate-methyl): A systemic fungicide with broad spectrum control. REI (varies with crop, see label), Group 1

Torino (cyflufenamid): Powdery mildew of cucurbits and strawberries. REI 4h, Group U6

Triathlon BA (Bacillus amyloliquefaciens D747): Microbial fungicide that can be used in the greenhouse. REI 4h, Group 44

TrilogyOG (neem oil): Various fungal diseases. REI 4h, Group NC

Trionic 4SC (triflumazole): Powdery mildew and Alternaria. Also labeled for greenhouse use. REI 24h, Group 3

Trivapro (benzovindiflupyr + azoxystrobin + propiconazole): Labeled for corn diseases. REI 12h, Groups 3 & 7 & 11

Ultra Flourish (mefenoxam): A fungicide active against Pythium, Phytophthora, and downy mildew. REI 48h, Group 4

Vanguard WG (cyprodinil): For management of diseases of onions. REI 12h, Group 9

Vivando (metrofenone): For powdery mildew. REI 12h, Group 50

ZeroTol 2.0OG (hydrogen dioxide): Preventive biocide labeled for greenhouse use. REI 0h (1 h spray), Group NC

Zampro 525SC (ametoctradin + dimethomorph):A fungicide for downy mildew and Phytophthora  diseases of potatoes and bulb, brassica, cucurbit, fruiting, and  leafy vegetables. REI 12h, Groups 40 & 45

Ziram (76DF, Excel)  (ziram): For use on tomatoes for anthracnose, septoria leaf spot and early blight. Do not use on cherry tomatoes. REI 48h, Group M3

Zing! (zoxamide): for managment of diseases of cucurbits, garlic, onions, potatoes and tomatoes. REI 12h, Groups 22 & M5

Soil Fumigation Outdoors

Soil fumigation is the most drastic measure that growers can perform to eradicate soil-borne pests and is often a method of last resort. Fumigants are general biocides; they are effective against fungi, bacteria, nematodes, soil insects, and weed seeds. They have several serious drawbacks:

  • Fumigants kill all organisms, even the beneficial ones that compete with or parasitize plant pathogens. They leave a biological vacuum which can be quickly reinfested with serious plant pathogens.
  • Fumigants have a high acute inhalation toxicity and are carcinogenic. They represent a hazard to humans, wildlife, and the environment.
  • Fumigants require specialized equipment and procedures to apply properly. They are usually applied by professional crop production services. Soil preparation, temperature, and rate of chemical will determine how effectively pests will be controlled.

Fall is the best time to fumigate. However, it can be very effective in spring with an appropriate post-treatment waiting period. Careful attention should be paid to soil temperature and moisture, as well as time of exposure as indicated on the product label. Plowing below the depth of treatment will mix non-treated and treated soil.

Read the label carefully before using fumigants. All chemical fumigants are restricted use and require a 5-day Entry Restricted Period after application. 

Telone C-17 (dichloropropene plus chloropicrin) or Telone II (dichloro-propene):  5.0-40 gal/A. Controls certain soil insects, nematodes, and soil-borne fungi. Read and follow the instructions on the label carefully.

InLine (dichloropropene plus chloropicrin):  13.0-20.5 gal/A. Controls certain soil insects, nematodes, and soil-borne fungi. Read and follow the instructions on the label carefully.

Vapam HL (sodium methyl dithiocarbamate): 50-100 gal/A. Controls weeds, soil insects, nematodes, and soil-borne fungi.  Read and follow the instructions on the label carefully.

Insect Management

A successful insect management program can best be accomplished by combining IPM techniques, such as accurate pest identification, scouting, monitoring, and action thresholds, with biological and preventative control practices and selective insecticide applications if needed.

Use scouting and monitoring techniques to help assess and quantify insect populations over time.

Insecticides should be used only when action thresholds have been exceeded or damaging insect populations are present. Action thresholds help minimize insecticide use and crop damage. Avoid making routine insecticide applications to crops without evidence of insect activity and damage. All insects have natural enemies which, if conserved, can help regulate pest populations. Whenever possible, use selective insecticides that spare beneficial organisms and target the pest you wish to control. Broad-spectrum insecticides should be used as a last resort. All insecticide applications should be made with ample water and with nozzles directed so that they provide thorough coverage of the plant parts where insects hide. Alternate between insecticide classes or families to help manage insect resistance and extend the life of available products.

Insect Identification

Become familiar with the biology and life-cycle of the major insect pests that attack crops on an annual basis. Understanding some basic insect biology often reveals when the pest is most vulnerable to control measures and helps lead to successful management efforts. Insects usually have either a simple life-cycle, where they grow from egg to nymph to adult, or a slightly more complex cycle, where they mature from egg to larva and then go through metamorphosis in the pupal stage before becoming adults. Insects damage plants either as nymphs/larvae or as adults, or in both immature and adult stages. Learn to recognize the important life-stages of major insect pests, and to  recognize the crop injury or damage they produce to help determine when control efforts are needed. You should also be able to identify common beneficial insects and their immature stages (i.e., lady bug larvae) to avoid accidentally targeting natural enemies with insecticides. There are dozens of minor and secondary insect pests that may attack crops on a less frequent basis. Growers should have unknown insects and minor pests identified (see Diagnostics for Plant Problems, page 66) when they are suspected of causing crop damage. Misidentification often leads to the application of an ineffective pesticide and extensive or chronic crop damage. The application of ineffective or unnecessary pesticides can often reduce the populations of beneficial organisms or natural enemies and lead to secondary insect or mite outbreaks. An accurate diagnosis of the problem early on can often prevent years of frustration and needless expense. See the Northeast Vegetable & Strawberry Pest Identification Guide for help with identification.

Scouting and Monitoring

Crops should be inspected or scouted for insects or damage in a systematic fashion, on a regular basis throughout the growing season. For many crops and pests, this may mean walking fields weekly, or even more frequently, especially during critical or vulnerable plant development stages. Crops should be scouted in a systematic fashion by walking in an "M" or "W" pattern as you crisscross the field. Select plants (i.e., 25 or 50) at random and quantify the pest damage or count the individual insects. Record the average number of insects or damage per plant for each field. Scouting crops always saves money in the long run by allowing for early pest detection, by reducing crop damage and by helping to maintain consistent quality. Sometimes scouting duties can be performed by other farm members or by hired consultants.

Monitoring insect populations with various types of traps (black light, pheromone, sticky, baited) can supplement or sometimes substitute for information normally gathered during crop scouting. Insect traps can help you quantify pest pressure that is difficult to see, such as the number of night flying (i.e., corn earworm) moths present. The number of insects captured in traps is often used to time scouting activities, predict future pest levels, or is used in conjunction with action thresholds to time sprays and help avoid crop damage.

Action Thresholds

Action thresholds tell you when to spray to prevent economic damage to the crop. They also help you avoid applying insecticides to crops when insect populations are low or no pests are present. Thresholds can be based on the number of insects found per plant, the amount of injury or damage per plant, or the number of insects captured in a trap. Using action thresholds helps improve insecticide timing and effectiveness, helps minimize the number of applications and associated costs, and helps reduce crop damage and resistance problems. Use action thresholds whenever possible to help you decide if and when a spray is needed. Some insect thresholds are provided in this publication. See your state's Extension IPM personnel for local action thresholds for specific pests.

Preventative Controls

As mentioned in the introduction to the general Pest Management section, there are many preventative management options, such as cultural, mechanical, physical, genetic and biological controls. These should be used whenever possible to help prevent insect pest problems. Preventative insect control options can be used alone or in combination to provide a complete management program. For example, plant inspections, eliminating weeds in the greenhouse, using screens, avoiding excess nitrogen applications, using plastic mulch and preserving natural enemies can combine to produce a very effective aphid management program. If the distance between fields is great enough, crop rotation (alone) for Colorado potato beetle and cucumber beetles can often keep these tough pests from reaching damaging levels for the entire season. However, if only nearby fields are available, CPB can be effectively controlled by the use of a combination of two or more alternative controls, such as short-distance crop rotation, intervening trap crops or plastic-lined trenches, row covers, organic mulches, flaming, and microbial controls. Many preventative controls are mentioned in crop-specific IPM manuals, individual pest fact sheets and on IPM websites.

Perimeter Trap Cropping utilizes a combination of control measures to concentrate and/or kill pests in the border area of the field. This technique involves planting one or more rows of an attractive plant species so that it completely encircles the less attractive main crop, and intercepts a migrating insect population. Often a chemical or microbial insecticide is used to spot-spray the perimeter trap crop (only), sparing beneficials on the main crop, and substantially reducing insecticide use. Perimeter trap cropping has been shown to be effective at controlling diamondback moth larvae on cabbage, using collards as the trap crop; pepper maggots on bell peppers or eggplant, using hot cherry peppers as the trap crop; and cucumber beetles on summer squash, winter squash, cucumbers, melons, and sometimes pumpkins, using Blue Hubbard squash or another Cucurbita maxima variety as the trap crop. This technique may prove useful on related crops and against additional pests in the future.

Insecticides

Follow the label specifications for application rates. If the rate suggested in this guide does not agree with the current label, follow the label recommendations. Amounts of pesticides are in lb/A (pounds per acre), oz/A (ounces per acre) or pt/A (pints per acre) of commercial formulation, not a.i. (active ingredient), unless otherwise stated. The percentage by weight or concentration of a.i. varies with different brands of pesticides. The label gives pounds of a.i. in each commercial preparation. For example, Lorsban 4E has 4 lb active ingredient/gallon of formulated material.

The amount of insecticide recommended per acre should not be changed when varying gallonage of water per acre. Make sure a pesticide is labeled for concentrate application before using a low volume sprayer, air or mist sprayer, aircraft or other concentrate application equipment.

Seed Treatments

Insecticide seed treatments may help protect your crop from soil insects and other early-season pests. Some of the seed treatments listed under various crops must be applied by a professionally licensed seed coating applicator. In some cases, the use or purchase of treated seed may be economical as it may result in a substantial reduction in pesticide use and increase the plant stand and yield in the field.

Resistance Management

Adult pests that survive an environmental hardship, such as the application of an insecticide, are likely to pass the trait that enabled them to survive on to their offspring. Repeat applications with the same type of pesticide will eventually remove almost all the susceptible individuals from a pest population and leave only those with the resistant gene. Because insects and mites go through generations quickly, resistance to an overused pesticide can develop in as little as three years.

To preserve the useful life of a pesticide, it is necessary to practice resistance management. The most effective way to extend the useful life of an effective product is to use it on a single pest generation only, and then on the next generation use a second pesticide with a different method of killing the pest (mode of action). On some pests particularly prone to developing resistance (i.e., Colorado potato beetle) it is best to use a product with a particular mode of action on one generation every second year only. To help select pesticides with a different mode of action, see chemical resistance groupings in Table 26 (page 108). These resistance group numbers, or IRAC codes, were developed by the Insecticide Resistance Action Committee (IRAC). Products with the same code (number and letter) indicate products with a common mode of action. For multiple applications to the same crop, select products from different resistance groups.

Once a pest develops resistance to a group of pesticides with a particular mode of action, a higher rate of a similar chemical from the same group usually will not control the insect.

NOTE: There is no cross-resistance between insecticides, herbicides and fungicides. For example, there is no problem when using material from the herbicide group 1 and an insecticide or fungicide from group 1.

There are many other techniques that can help delay the onset of resistance. Most resistance management techniques help minimize the use of pesticides so that a lower proportion of each pest generation is exposed to the toxin.

  • Integrate chemical control with effective cultural, mechanical, physical, and genetic management options.
  • Use biological/microbial control agents or other selective pesticides to preserve natural enemies and help minimize the number of repeat applications.
  • Scout, monitor and use action thresholds to ensure that applications are necessary.
  • Good spray coverage helps do the job right the first time and avoids unnecessary repeat applications: use the proper size nozzles and the correct angle or orientation and an adequate amount of water per acre.
  • Time the application so that the most vulnerable insect life stage is exposed to the spray.
  • Use spot sprays, perimeter trap crop treatments, refuge plantings, and other methods that prevent the entire field or population from being treated to help preserve susceptible individuals.

Toxicity Rating of Insecticides

Insecticides vary greatly in their toxicity to humans and the environment. The toxicity of the insecticide is usually stated in the precaution on the label. For example, a skull and crossbones figure and the signal word "Danger" are always found on the label of highly toxic (Toxicity Class I) materials. Those of medium toxicity (Toxicity Class II) carry the signal word "Warning." The least toxic materials (Toxicity Class III) have the signal word "Caution." The toxicity of a pesticide is expressed in terms of oral and dermal LD50. LD50 is the dosage of poison that kills 50% of test animals (usually rats or rabbits) with a single application of the pure pesticide for a given weight of the animal (mg/kg of body weight). The lower the LD50 value, the more toxic the material. Oral LD50 is the measure of the toxicity of pure pesticide when administered internally to test animals. Dermal LD50 is the measure of the toxicity of pure pesticide applied to the skin of test animals. Generally, an oral exposure is more toxic than a dermal one.

Protecting Honeybees and Native Pollinators

Honeybees and native pollinators visit vegetable crops during flowering and pollen shed. In crops such as cucurbits, their activity is crucial to the success of the crop. In other crops such as sweet corn or potato, bees are among many beneficial insects that seek out pollen or nectar resources as a food source, but crop yield does not depend upon their activity.  Populations of honeybees and native pollinators have declined worldwide in recent years. Many factors have contributed to their decline. Pesticides applied to crops is one of these factors.

Pesticides applied to protect vegetable crops can affect pollinators through multiple routes of exposure: direct contact with sprays, contact with treated surfaces, pesticide-contaminated dust or pollen particles that are collected or adhere to the body of the insect (and may be taken back to hive), and ingestion of pesticide-contaminated nectar. Decisions made by the farmer make a difference in the exposure of bees and other beneficials to toxic levels of pesticides. While pesticides applied to crops are only one among many factors that threaten pollinators, this is one factor that growers can do something about. Taking precautions to minimize pesticide poisoning of pollinators in all crops is an important responsibility of all pesticide applicators.

Steps that can reduce pesticide exposure of pollinators:

Timing.  Avoid applications when crop or weeds are in bloom. In crops that bloom over long periods, make applications late in the day or at night when pollinators are not foraging, and so that there is sufficient drying time before foraging begins. Control weeds.

Formulation. Wettable powders, dusts and microencapsulated products have a greater toxic hazard than emulsifiable concentrates (or other liquid formulation with active ingredient in solution). Products that do not have acute toxicity but could cause injury to immature bees if carried back to the hive should not be applied in particulate form; this includes insect growth regulators.

Drying time before exposure. Some products are highly toxic when wet, but much less so after the pesticide is dried. Spinosyns have this characteristic. Apply when there will be adequate drying time (usually 2-3 hours, depending on weather conditions and crop canopy) before pollinator activity.

Drift. Avoid drift on non-target areas near the field where blooming plants may be located. Windspeed and application equipment both influence drift.

Mode of application. Soil and seed applications reduce exposure compared to foliar applications, unless plant uptake of the active ingredient produces residues in pollen or nectar. In the case of neonicotinoids, there is evidence that foraging bees may receive sublethal doses in pollen and nectar when cucurbit crops were treated with a systemic at early growth stages. This effect appears to be reduced by using lower rates and applying as early as possible, but may not be entirely eliminated by these methods. A sublethal dose may make bees more vulnerable to other stressors, or may combine with doses from contact with other treated plant material.

Acute toxicity. Avoid applying insecticides rated as High or Medium directly to bees that are actively foraging on blooming crop or weeds. See Table 26 (page 108) for information on insecticide active ingredients and toxicity. EPA registration includes an acute, single-dose laboratory study designed to determine the quantity of pesticide that will cause 50% mortality (LD50) in a test population of bees.

Read the label for bee hazard rating. If a pesticide is used outdoors as a foliar application, and is toxic to pollinating insects, a “Bee Hazard” warning has generally been required to be included in the Environmental Hazards section of the label. The EPA bee toxicity groupings and label statements are as follows:

High (H) Bee acute toxicity rating: LD50 = 2 micrograms/bee or less. The label has the following statement: "This product is highly toxic to bees and other pollinating insects exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees or other pollinating insects are visiting the treatment area."  If the residues phrase is not present, this indicates that the pesticide does not show extended residual toxicity.
Moderate (M) Product contains any active ingredient(s) with acute LD50 of greater than 2 micrograms/bee but less than 11 micrograms/bee. Statement: "This product is moderately toxic to bees and other pollinating insects exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product if bees or other pollinating insects are visiting the treatment area."
Low (L) All others. No bee or pollinating insect caution required.

In this guide, Table 26 (Information about Insecticides and Miticides) gives the bee toxicity rating (H, M or L) for each active ingredient. In the Insect Management section for each crop, the bee toxicity rating is given for each insecticide listed.

Insecticides Alphabetical Listing by Trade Name

The symbol * indicates a Federally restricted-use pesticide

The symbol OG indicates a pesticide that has been listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production.

Some products are described in detail as examples for a given active ingredient (AI). For more information on other products with the same AI, refer to the example. Always refer to the specific product label before applying any product.

All tolerances for chlorpyrifos in food crops were revoked in 2022, therefore products containing chlorpyrifos (e.g. Lorsban) cannot be applied to any food crop and growers CAN NOT use up existing stock.

At the time of writing, all products listed were registered in at least one New England state. Check registration status in your state before using any product.

Abacus* (abamectin): See Agri-Mek for more information.  

Abamex* (abamectin): See Agri-Mek for more information.

Abba* (abamectin): See Agri-Mek for more information.

Acenthrin* (acephate + bifenthrin): A mixture of two broad-spectrum neurotoxins. See Orthene and Brigade for more information on active ingredients in this product.

Acephate (acephate): See Orthene for more information.

Acramite (bifenazate): A selective miticide which acts on contact as a nerve toxin with knockdown activity and long residual. Registered as a foliar spray for control of mites on cucurbits, eggplant, okra, peppers, field-grown tomatoes (for greenhouse tomatoes, see bifenzate product, Floramite), succulent beans and peas, and herbs. Relatively safe on beneficials. (Group 25, REI 12h)

Acronyx (imidacloprid): See Admire for more information.

Actara (thiamethoxam): A systemic neonicotinoid with translaminar activity, registered for use as a foliar spray for control of aphids, flea beetles, leafhoppers, whiteflies, and other pests on brassicas, cucurbits, fruiting vegetables, globe artichoke, leafy vegetables, mint, and root and tuberous vegetables. Do not use in greenhouses or on plants grown for use as transplants. Highly toxic to bees. (Group 4A, REI 12h)

Admire (imidacloprid): A systemic neonicotinoid, registered for use in soil, seed piece, and foliar applications. Labeled for use on cucurbits, herbs, brassicas, legumes, roots, bulbs, tubers, corms, globe artichoke, and fruiting and leafy vegetables for control of aphids, flea beetles, leafhoppers, whiteflies, thrips and Colorado potato beetle. Also labeled for use in greenhouses on mature cucumber and tomato plants to control aphids and whiteflies. Do not apply to non-soil media or in hydroponic systems. Specific labeled application methods vary by crop. Highly toxic to bees. (Group 4A, REI 12h)

Advise (imidacloprid): See Admire for more information.

AgreeOG (Bacillus thuringiensis subspecies aizawai strain GC91): See XenTari for more information.

Agri-Mek* (abamectin): A locally systemic, selective chloride channel activator insecticide and miticide, derived from a metabolite of a soil bacterium, Streptomyces avermitilis. Registered for use as a foliar spray with translaminar activity to control spider mites on celeriac and sweet corn, thrips and leafminers on onions (bulb & green), and mites and leaf miners on cucurbits, dry beans, fruiting vegetables, herbs, tubers and corms, and non-brassica leafy greens. Also controls Colorado potato beetle and tomato and potato psyllid on fruiting vegetables and potatoes. Labeled for use on commercially produced greenhouse tomato for leafminer, mites, thrips, tomato psyllid, and tomato pinworm. Highly toxic to bees. (Group 6, REI 12h)

Akari (fenpyroximate): See Portal for more information.

Alias (imidacloprid): See Admire for more information.

Altus (flupyradifurone): See Sivanto for more information.

Amazin PlusOG (azadirachtin): See Azatin for more information.

Ambush* (permethrin): See Pounce for more information.

AmTide Imidacloprid (imidacloprid): See Admire for more information.

Anarchy (acetamiprid): See Assail for more information.

AncoraOG (Isaria fumosorosea Apopka Strain 97): See PFR-97 for more information.

Archer (pyriproxyfen): See Esteem for more information.

Arctic* (permethrin): See Pounce for more information.

Arvida (acetamiprid): See Assail for more information.

Asana* (esfenvalerate): A broad-spectrum, pyrethroid insecticide that works by contact and ingestion. Labeled for foliar applications on artichoke, beans, brassicas, carrots, cucurbits, fruiting vegetables, roots, sweet corn and potatoes to control a wide variety of pests. Extremely toxic to fish and aquatic invertebrates and highly toxic to bees. (Group 3, REI 12h)

Assail (acetamiprid): A selective neonicotinoid, with translaminar activity, that controls sucking and chewing insects through contact and ingestion. Registered to control aphids, whitefly and other pests on asparagus, leafy vegetables, cole crops, fruiting vegetables, cucurbits, sweet corn, and succulent peas and beans. Also labeled for control of thrips on bulb vegetables, as well as aphids, Colorado potato beetle, flea beetle and other pests on tuberous and corm vegetables. (Group 4A, REI 12h)

Athena* (abamectin + bifenthrin): A mixture of a broad-spectrum pyrethroid and bacterium-derived chloride channel activator. See Agri-Mek and Brigade for more information on active ingredients in this product.

Avaunt (indoxacarb): A sodium channel blocker with translaminar activity that causes paralysis and death after being ingested on plant tissue. Labeled for use as a foliar spray on brassicas, cucurbits, fruiting vegetables, beets, leafy greens, leafy petioles, mint, and tubers and corms to control caterpillars. Also registered to control European corn borer and fall armyworm in whorl and be used in irrigation systems except for application to potatoes and sweet corn. Relatively safe for beneficials, but toxic to bees exposed to direct treatment. (Group 22, REI 12h)

Averland* (abamectin): See Agri-Mek for more information. 

Aza-DirectOG (azadirachtin): See Azatin for more information.

AzaGuardOG (azadirachtin): See Azatin for more information.

AzaMaxOG (azadirachtin): See Azatin for more information.

AzatinOG (azadirachtin): A natural insect growth regulator extracted from the seeds of the neem tree, works by contact or ingestion against immature insect stages and has anti-feedant properties. Has some systemic activity and can be taken up by plant roots; may be used as a transplant drench. Registered for use as a foliar spray in field and greenhouse on all vegetable and vegetable transplants and herbs to control multiple pests. Short residual. Note: Azatin O is OMRI certified, but Azatin XL is not. (Group un, REI 4h)

AzatrolOG (azadirachtin): See Azatin for more information.

AzeraOG (azadirachtin + pyrethrin): See Azatin and Pyganic for more information.

Aztec* (beta-cyfluthrin + tebuprimphos): A mix of pyrethroid and organophosphate chemistries registered (VT only) for soil applications in sweet corn and popcorn for control of corn rootworms, cutworms, wireworms, seedcorn maggot, seedcorn beetle, and white grubs. (Group 1B, REI 48h)

Baythroid* (beta-cyfluthrin): A broad-spectrum, pyrethroid insecticide that works by contact or ingestion, labeled for foliar applications on brassicas, cucurbits, fruiting vegetables, leafy greens, dry beans, potatoes and other tubers and corms, carrots, radishes, and sweet corn for contact control of caterpillars, flea beetles, stink bugs, and other pests. Extremely toxic to fish and aquatic invertebrates and highly toxic to bees. (Group 3, REI 12h)

Batallion* (bifenthrin): See Brigade for more information

Belay (clothianidin): A neonicotinoid with long residual control, registered for use in foliar and soil applications on brassicas, cucurbits, and fruiting and leafy vegetables. Becomes systemic when applied to soil, and has translaminar activity when applied to foliage. Labeled to control aphids, flea beetles, stink bugs, leafhoppers, cucumber beetles, Colorado potato beetle, and other pests. Also labeled for use on tuberous and corm vegetables in foliar, seed piece and soil applications to control aphids, Colorado potato beetle, wireworms, white grubs, and other pests. Highly toxic to bees. (Group 4A, REI 12h)

Beleaf (flonicamid): A pyridinecarboxamide with translaminar activity that works by contact and ingestion. Feeding stops rapidly and mortality will follow. Labeled for use on brassicas, cucurbits, fruiting vegetables, leafy greens, tubers and corms, root vegetables, greenhouse cucumbers and tomatoes and mint for selective control of aphids, plant bugs and greenhouse whitefly. (Group 29, REI 12h)

Belt (flubendiamide): Note: All flubendiamide registrations were canceled by the EPA in 2016. Growers may use up existing stock. A diamide, active by insect larval ingestion, leading to a rapid cessation of feeding followed by death. Labeled for use as a foliar spray on brassicas and turnip greens, corn, cucurbits, fruiting vegetables, and legumes to control caterpillars. Not labeled for use in enclosed structures, such as greenhouses. (Group 28, REI 12h)

Besiege* (chlorantraniliprole + lambda-cyhalothrin): See Coragen and Warrior for more information.

Bifenture* (bifenthrin): See Brigade for more information.

Blackhawk (spinosad): See Entrust for more information.

Bifen* (bifenthrin): See Brigade for more information.

BiobitOG (Bacillus thuringiensis subspecies kurstaki strain ABTS-351): See Dipel for more information.

BioCeresOG (Beauveria bassiana Strain ANT-03): See Mycotrol for more information.

Bonide Garden Dust (sulfur): See Microthiol Disperss for more information.

Botanigard (Beauveria bassiana Strain GHA): See Mycotrol ESO for more information. Not approved for organic production. Notes: ES formulation may be phytotoxic on tomatoes. Maxx formulation contains pyrethrins.

Brigade* (bifenthrin): A broad-spectrum, pyrethroid insecticide and miticide. Labeled for use as a foliar spray on a wide variety of crops to control aphids, flea beetles, leafhoppers, stink bugs, caterpillars and several other pests. Extremely toxic to fish and aquatic invertebrates and highly toxic to bees. Prohibited in areas where application may result in exposure to endangered species. (Group 3A, REI 12h)

Brigadier* (bifenthrin + imidacloprid): See Brigade and Admire for more information.

BT NowOG (Bacillus thuringiensis subsp. kurstaki strain EVB 113-19): See Dipel for more information.

Captiva (capsicum oleoresin extract + garlic oil): A repellant and insecticide made from concentrated plant extracts. Works by contact. Has anti-feedant, anti-egg laying, and irritant activity, and weakens cuticles of immature stages of some insect and mite pests. Registered for foliar applications in field and greenhouse on all food crops including greenhouse vegetable and transplant production to repel or suppress soft-bodied pests. (No resistance classification, REI 4h)

Capture* (bifenthrin): A broad-spectrum, pyrethroid insecticide and miticide, labeled for soil applications. Capture LFR can be mixed directly with liquid fertilizer or with water. Registered for use on a wide variety of crops to control wireworm, grubs, root maggot, cutworm, flea beetle larvae, and other soil dwelling pests. Extremely toxic to fish and aquatic invertebrates and highly toxic to bees. Prohibited in areas where application may result in exposure to endangered species. (Group 3A, REI 12h)

Carbaryl (carbaryl): See Sevin for more information.

Citation (cyromazine): Labeled for vegetable transplants grown for consumer use. See Trigard for more information.

Clinch Ant Bait* (abamectin): A selective chloride channel activator insecticide that kills ants by ingestion, and acts to cease viable egg production. Registered as a soil treatment in various crops to control fire ants. Long residual. (Group 6, REI 12h)

Closer (sulfoxaflor):  See Transform for more information. Note: After being cancelled in 2015, sulfoxaflor registrations have been reinstated by the EPA under limited-use restrictions.

Confirm (tebufenozide): A selective insect growth regulator that induces a premature lethal molt within hours of ingestion. Labeled for use on brassicas, leafy vegetables, turnips, and fruiting vegetables and mint to control caterpillars. Not disruptive to beneficials and bees. (Group 18, REI 4h)

Consero* (spinosad + gamma-cyhalothrin): Labeled for corn and legumes. See Entrust and Declare for more information.

Coragen (chlorantraniliprole): A diamide that has contact activity, but is most effective through ingestion of treated plant material. Insects rapidly stop feeding, become paralyzed and typically die within 1-3 days. Becomes systemic when applied to soil. Labeled for use as a foliar spray on artichoke, asparagus, bulb vegetables, corn, herbs, legumes, and roots and tubers to control caterpillars; and potatoes to control caterpillars and Colorado potato beetle. Also labeled as a foliar, drip irrigation, and soil treatment on brassicas, cucurbits, and fruiting and leafy vegetables to control caterpillars, leafminer and whitefly larvae, and Colorado potato beetle. Also labeled as a transplant water treatment for suppression of cabbage root maggot in leafy brassicas. Effective against difficult to control caterpillars such as beet and fall armyworm. Relatively safe for beneficials and non-target organisms. (Group 28, REI 4h)

Cormoran (novaluron + acetamiprid): See Rimon and Assail for more information.

CoStarOG (Bacillus thuringiensis subsp. kurstaki strain SA-12): See Dipel for more information.

Couraze (imidacloprid): See Admire for more information.

Cruiser (thiamethoxam): A systemic neonicotinoid commercial seed treatment that is taken up by the seedling plant and controls chewing and sucking insects through contact and ingestion. Labeled for use on cucurbits, legumes and potatoes to control aphids, leafminers, wireworms and several other pests, including Mexican bean leaf beetle and thrips on legumes and Colorado potato beetle on potatoes. Highly toxic to bees. (Group 4A, REI 12h)

CrymaxOG (Bacillus thuringiensis subspecies kurstaki strain EG7841): See Dipel for more information.

Damoil (mineral oil): See Suffoil-X for more information.

Danitol* (fenpropathrin): A pyrethroid insecticide-miticide with contact activity. Labeled for use on cucurbits, fruiting vegetables, brassicas and peas to control a wide variety of pests including aphids, caterpillars, flea beetles, spotted wing drosophila, Colorado potato beetle, and stink bugs. Extremely toxic to fish and aquatic organisms, and highly toxic to bees. (Group 3A, REI 24h)

Deadline M-Ps (metaldehyde): A toxic bait for slugs and snails. Labeled for use as a soil surface treatment for most vegetable crops. Not for direct application to or contamination of edible portions of the plant; to be applied as a band treatment between rows after formation of edible parts. Long-lasting; resistant to rain and watering. (No resistance classification, REI 12h)

Debug Turbo (azadirachtin + neem oil): See Azatin for more information.

Declare* (gamma-cyhalothrin): A microencapsulated broad-spectrum pyrethroid that acts on contact and via ingestion. Registered for use on brassicas, sweet corn, popcorn, cucurbits, fruiting vegetables, legumes, lettuce, onion, garlic, tuberous and corm vegetables to control a wide variety of pests. Highly toxic to bees and extremely toxic to aquatic organisms. (Group 3A, REI 24h)

Defcon* (beta-cyfluthrin + tebupirimfos): For control of soil insects in corn. See Baythroid and Aztec for more information.

DeliverOG (Bacillus thuringiensis subsp. kurstaki): See Dipel for more information.

Delta Gold* (deltamethrin): A broad-spectrum, pyrethroid insecticide. Labeled for use on corn, cucurbits, bulb, fruiting, root, tuberous and corm vegetables, and globe artichoke to control a wide variety of pests. Extremely toxic to fish and aquatic invertebrates, and highly toxic to bees. (Group 3A, REI 12h)

DES-XOG (insecticidal soap): See M-Pede for more information.

Diazinon* (diazinon): An organophosphate with contact activity, labeled for use as a soil spray to be broadcast before planting and incorporated into the soil. Labeled for use on succulent legumes, tomatoes, and specific brassicas, melons, roots, and leafy greens to control cutworms, wireworms, and on some crops mole crickets and/or root maggots. Not to be used in greenhouses. Highly toxic to bees. (Group 1B, REI 2 to 4 days depending on crop)

Dimate (dimethoate): See Dimethoate for more information.

Dimethoate (dimethoate): A broad-spectrum organophosphate with systemic and contact activity against piercing, sucking, and chewing insects and mites. Labeled for use on asparagus, beans, some brassicas, leafy greens, melons (except watermelons), celery, fruiting crops, succulent beans. Useful for control of pepper maggot in peppers. Not to be used in greenhouses. Highly toxic to bees. (Group 1B, REI 48h)

Dimilin* (diflubenzuron): A selective insect growth regulator that disrupts the molting process of insect larvae. Labeled for use on peppers to control armyworms and pepper weevils. Not disruptive to bees or other beneficial insects. (Group 15, REI 12h)

DipelOG (Bacillus thuringiensis subsp. kurstaki): A bacterium-derived insecticide that works by ingestion. Labeled for use on root, tuber, bulb, leafy green, brassica, legume, fruiting and cucurbit vegetables to control caterpillars. Safe for bees and beneficial insects. Note: Dipel ES is not OMRI listed, Dipel DF is. (Group 11A, REI 4h)

Discipline* (bifenthrin): See Brigade for more information.

Distance IGR (pyriproxyfen): An insect growth regulator that works by suppressing the development of the embryo within the egg and inhibiting metamorphosis of nymphs, larvae, and pupae into adults. Works by contact and ingestion. Labeled for use as a foliar spray with translaminar activity when used on indoor-grown fruiting vegetables to control greenhouse, silverleaf, and sweet potato whitefly, as well as fungus gnats and shore flies when applied as a soil drench. (Group 7D, REI 12h)

Durivo (chlorantraniliprole + thiamethoxam): See Coragen and Actara for more information.

Ecotrol PlusOG (rosemary oil + peppermint oil + geraniol): A broad-spectrum, plant-based granular insecticide that works on contact. Labeled for foliar application to a variety of crops for control of aphids, beetles, plant bugs,  whiteflies, mites, thrips, and early stages of caterpillars. This product is exempt from EPA pesticide registration requirements.

Ecotrol G2OG (rosemary oil + peppermint oil): A broad-spectrum, plant-based granular insecticide, formulated from plant oils on ground corn cob. Incorporate as a band or with seeds at or after planting. Labeled for use on a variety of crops for control of wireworms, cutworms, root maggots, and symphylans. This product is exempt from EPA pesticide registration requirements.

EcozinOG (azadirachtin): See Azatin for more information.

Elevest (bifenthrin + chlorantraniliprole): See Brigade and Coragen for more information.

Empower* (bifenthrin): See Brigade (for foliar applications) or Capture (for soil applications) for more information. Granular formulations may not be applied in coastal counties.

Endeavor (pymetrozine): See Fulfill for more information.

Endigo* (lambda-cyhalothrin + thiomethoxam): See Warrior and Actara for more information.

EntrustOG (spinosad): A nerve and stomach poison derived from the soil bacterium, Saccharopolyspora spinosa. Registered for use as a foliar spray with some translaminar activity on asparagus, brassicas, bulb vegetables, corn, cucurbits, fruiting vegetables, herbs, leafy greens, legumes, roots, and tubers to control lepidopteran larvae, Colorado potato beetle, leafminers, thrips and other pests. Helps conserve beneficial predators, but may be toxic to some parasites of insect pests. Toxic to bees for three hours following treatment. (Group 5, REI 4h).

Esteem (pyriproxyfen): An insect growth regulator that works by suppressing the development of the embryo within the egg and inhibiting metamorphosis of nymphs, larvae, and pupae into adults. Does not control adult insects. Labeled for use as a foliar spray with translaminar activity on dry bulb onions to control onion and Western flower thrips and on legumes to control silverleaf and sweet potato whitefly. Not for use in irrigation systems. (Group 7D, REI 12h)

Ethos* (bifenthrin + Bacillus amyloliquefaciens strain D747): Group 3A insecticide + biofungicide for in-furrow treatment of soil pests and disease

Evergreen (pyrethrins + piperonyl butoxide): See Pyganic and Pyronyl Crop Spray for more information. 

Exirel (cyantraniliprole): A diamide that has some contact activity, but is most effective through ingestion. Labeled for use as a foliar spray on brassica, bulb, cucurbit, fruiting, and leafy vegetables, as well as greenhouse-grown eggplant, pepper, and tomato to control sucking and chewing insects including lepidopteran larvae, aphids, flea beetle, leafminers, thrips, and whitefly. Highly toxic to bees. (Group 28, REI 12h)

Fanfare* (bifenthrin): See Brigade for more information.

Fastac* (alpha-cypermethrin): A broad-spectrum pyrethroid insecticide. Labeled for foliar applications on brassicas, sweet corn, cucurbits, fruiting vegetables, leafy vegetables, and legumes to control a wide variety of pests. Extremely toxic to fish and aquatic invertebrates and highly toxic to bees. (Group 3A, REI 12h)

Flagship (thimethoxam): For use in greenhouses on vegetable transplants for resale only. See Actara for more information.

Floramite (bifenazate): A selective contact carbazate miticide with knockdown activity and long residual. Labeled for use on greenhouse tomatoes (for field tomatoes, see bifenazate product, Acramite) to control mites. Relatively safe on beneficials. (Group un, REI 12h)

Force* (tefluthrin): A pyrethroid that works by ingestion and contact. Labeled for use in band and in-furrow soil applications at planting on sweet corn and popcorn to control wireworms, seedcorn maggots, white grubs and other soil insect pests. (Group 3A, REI 48h)

Fulfill (pymetrozine): A selective hemipteran feeding blocker that works primarily by ingestion, but has some contact activity. Labeled for use as a foliar spray on potatoes and other tuberous roots and corms, asparagus, brassicas, cucurbits, and fruiting and leafy vegetables to control aphids. Translaminar, long residual. Low toxicity to beneficials, including bees, but do not apply to bees that are actively foraging. (Group 9B, REI 12h)

Fyfanon (malathion): See Malathion for more information.

GemstarOG (nuclear polyhedrosis virus of Helicoverpa zea): A selective biopesticide for control of Helicoverpa zea on several vegetables, fruits, and field crops. Larvae ingesting the virus stop feeding within several days, become pale and lethargic, and then die as the virus replicates throughout their bodies. Frequent application at low rates is usually more effective than infrequent application at high rates. (Group un, REI 4 h)

GF-120 Naturalyte Fruit Fly BaitOG (spinosad): An insecticidal bait labeled for use as a foliar and soil spray on vegetable and food crops to control tephritid fruit flies. Highly toxic to bees if directly applied. (Group 5, REI 4h)

GnatrolOG (Bacillus thuringiensis subsp. israelensis): A bacterium-derived larvicide labeled for use as a soil drench on vegetable plants including brassicas, tomatoes, leafy vegetables, cucumbers, peppers, and eggplants to control fungus gnat larvae. (Group 11, REI 4h)

Golden Pest Spray OilOG (soybean oil): A soybean-derived horticultural oil that works as a contact insecticide, as well as a feeding and oviposition deterrent. Labeled for use in sweet corn for control of earworm root worms and fall armyworm. Also labeled for use on a range vegetable crops to control other soft-bodied insects. (No resistance classification, REI 4h)

GrandevoOG (Chromobacterium subtsugae strain PRAA4-1): A selective biological insecticide/miticide that works as a stomach poison upon ingestion. Labeled for use as a foliar spray or in chemigation for control of certain caterpillars, foliage-feeding beetles, aphids, whiteflies, mites, leafhoppers and thrips on many vegetable crops. (No resistance classification, REI 4h)

Grizzly* (lambda-cyhalothrin): See Warrior for more information.

Harvanta (cyclaniliprole): A broad-spectrum diamide. Labeled for use in leafy vegetables, heading brassicas and leafy and fruiting vegetables for caterpillars, flea beetles, thrips, stink bugs, and aphids (Group 28, REI 4h)

HeligenOG (Helicoverpa zea nucleopolyhedrovirus ABA-NPV-U): See Gemstar for more information.

Hero* (bifenthrin + zeta-cypermethrin): See Brigade and Mustang for more information.

Holster* (zeta-cypermethrin): See Mustang for more information.

Imidan (phosmet): A broad-spectrum organophosphate labeled for use on potato and sweet potato to control Colorado potato beetle, European corn borer, flea beetle, potato leafhopper, and other pests. Potatoes and sweet potatoes must be harvested mechanically. Highly toxic to bees. (Group 1B, REI 5 days)

Intrepid (methoxyfenozide): A selective diacylhydrazine insect growth regulator that works by ingestion. Labeled for use on leafy brassicas, other leafy greens, cucurbits, fruiting vegetables, root vegetables, sweet potato, globe artichoke, green onions, legumes, popcorn, and herbs. Controls caterpillars by causing a premature and incomplete lethal molt. Safe for bees and other beneficial insects. (Group 18, REI 4h)

Intrepid Edge (methoxyfenozide + spinetoram): See Intrepid and Radiant for more information.

Inspirato (methoxyfenozide): See Intrepid for more information.

Intruder (acetamiprid): See Assail for more information.

Invertid (methoxyfenozide): See Intrepid for more information.

JavelinOG (Bacillus thuringiensis subsp. kurstaki): See Dipel for more information. 

JMS Stylet OilOG (paraffinic oil): See Suffoil-X for more information. Note: Organic JMS Stylet Oil is OMRI listed; JMS Stylet Oil is not.

Kanemite (acequinocyl): A selective miticide with knockdown and residual activity. Labeled for use as a foliar spray on fruiting vegetables, edible-podded beans, and edamame to control two-spotted spider mite, and on cucurbits, succulent shelled beans, and okra to control two-spotted spider mites and broad mites. Shows efficacy on all mite life stages. Relatively harmless to most predaceous mites and beneficial insects, (Group 20B, REI 12h)

Kilter* (imidacloprid + lambda-cyhalothrin): See Admire + Warrior for more information.

Knack (pyriproxyfen): An insect growth regulator that works by contact on immature stages. No activity against adult insects. Labeled for use as a foliar spray with translaminar activity on brassicas, cucurbits, succulent and dry legumes, and roots and tubers to control various whitefly species. Also labeled for use on tomatoes to control whiteflies, armyworms, tomato pinworm, thrips and other pests; for other fruiting vegetables to control whiteflies, cabbage looper, green peach aphids, and tobacco hornworm; and for bulb vegetables to control onion thrips. (Group 7C, REI 12h)

Kontos Greenhouse and Nursery (spirotetramat): For use in greenhouses on vegetable transplants for resale only. See Movento for more information.

Lada (imidacloprid): See Admire for more information.

Lambda-Cy* (lambda-cyhalothrin): See Warrior for more information.

Lambda-T2* (lambda-cyhalothrin): See Warrior for more information.

LambdaStar*(lambda-cyhalothrin): See Warrior for more information.

Lamcap* (lambda-cyhalothrin): See Warrior for more information.

Lannate* (methomyl): A broad-spectrum carbamate insecticide with translaminar activity. Works on contact, and short-term via ingestion of treated foliage, on all pest life stages. Registered as a foliar spray on a variety of crops for control of aphids, caterpillars, and beetles, including brown marmorated stinkbug. Effective on melon aphids. Other aphids and some caterpillars, such as diamondback moth and cabbage loopers, tend to be resistant. Short residual. Highly toxic to bees. (Group 1A, REI 48h)

Leap (Bacillus thuringiensis subspecies kurstaki strain ABTS-351 + methyl salicylate): Selective insecticidal bacterium and a plant extract linked to disease control.

Leprotec (Bacillus thuringiensis subspecies kurstaki strain EVB-113-19): See Dipel for more information.

Leverage* (imidacloprid + beta-cyfluthrin): See Admire and Baythroid for more information.

Macho (imidacloprid): See Admire for more information.

Magister (fenazaquin): A mitichondial electron transport inhibitor (METI) that acts on eggs, immature, and adult mites and certain insects. Also Group 39 fungicidal activity.  Highly toxic to bees, fish, and aquatic invertebrates (Group 21A, REI 12h).

Magus (fenazaquin): See Magister for more information.

MajesteneOG (Heat-killed Burkholderia spp.): See Venerate for more information. Also has a 2(ee) use as a seed treatment, in-furrow at planting, or as a soil drench for the suppression of wireworms, white grubs, as well as root knot, dagger, cyst, stunt, and lesion nematodes attacking potato and sweet potato. (Group un, REI 4 h)

Malathion (malathion): An organophosphate insecticide that acts by contact as a nerve toxin. Registered as a foliar spray on a variety of vegetable crops to control a wide range of insect pests. Highly toxic to bees. (Group 1B, REI 12h to 2 days, depending on crop)

Malice (imidacloprid): See Admire for more information.

Mallet (imidacloprid): Labeled for use inside greenhouses through irrigation or drench application or as a foliar spray for vegetable transplants and nursery stock for resale only. See Admire for more information. Refer to specific product label before applying. 

Mantra (imidacroprid): For use in greenhouses on vegetable transplants for resale only. See Admire for more information.

Manticor (bifenthrin + pyraclostrobin): For in-furrow application in sweet corn; a group 3A insecticide + group 11 fungicide. See for more information Brigade for more information.

Marathon (imidacloprid): Labeled for use inside greenhouses for vegetable transplants and nursery stock for resale only. See Admire for more information.

Met52 (Metarhizium anisopliae Strain F52): Composed of spores of a naturally occurring insect pathogenic fungus. Spores attach to the insect and hyphae penetrate the exoskeleton, growing inside and causing death, usually taking 3-7 days from exposure, depending on temperature. Labeled for use as a foliar spray or soil drench on field and greenhouse onions to control thrips, and on field and greenhouse cucurbits, celery, lettuce, spinach, peppers, and tomatoes to control thrips, whiteflies, and mites. Persistence will generally be higher when incorporated into soil but may be effective for a few months even in foliar applications. The EPA reports that M. anisopliae strain F52 is not harmful to earthworms or to such beneficial insects as lady beetles, green lacewings, parasitic wasps, honey bee larvae, and honey bee adults. (Group un, REI 0h when mechanically soil-incorporated, 4h otherwise)

Microfine sulfurOG (sulfur): See Microthiol Disperss for more information.

Microthiol DisperssOG (sulfur): Micronized wettable sulfur for use on a variety of crops to control mites. (Group M2 fungicide, no insect resistance classification, REI 24h)

Millenium (Steinernema carpocapsae): A biological control for ground dwelling insects and certain borers. Entomopathogenic nematodes must be refrigerated and can not be frozen. See label for compatibility with various pesticides. (Group un, No REI).

Minecto Pro (abamectin + cyantraniliprole): See Agri-Mek and Verimark for more information.

Mite-E-Oil (mineral oil): See Suffoil-X for more information.

Mocap* (ethoprop): An organophosphate nematicide-insecticide that works as a nerve toxin. Labeled for soil applications on mint, potatoes, and sweet potatoes to control various soil pests. Extremely toxic to birds. (Group 1B, REI 48h)

Molt-XOG (azadirachtin): See Azatin for more information.

Montana (imidacloprid): See Admire for more information.

Movento (spirotetramat): A tetronic acid derivative insecticide that works primarily by ingestion against immature pest stages. Fertility of adult stages may also be reduced. It is taken up by leaves and translocated to become fully systemic. Registered as a foliar spray on several vegetable crops to control thrips, aphids, swede midge and other pests. Potentially toxic to bee larvae through residues in pollen and nectar, but not to adult honeybees. Not for use in greenhouses. (Group 23, REI 24h)

M-PedeOG (potassium salts of fatty acids): An insecticidal soap that works by contact as an insecticide, miticide, and fungicide. Registered for use as a foliar spray for most vegetable and herb crops for control of a variety of insect pests; also active against powdery mildew. Must be applied directly to and thoroughly cover target insects. Avoid treatment when plants are stressed. Can be phytotoxic to some crops; test on small plot. May harm beneficials. (No resistance classification, REI 12h)

Mustang* (zeta-cypermethrin): A pyrethroid insecticide that works by contact as a nerve toxin.  Registered for use as a foliar spray on globe artichoke, brassicas, bulbs, sweet corn, cucurbits, fruiting vegetables, leafy greens, legumes, roots, and tubers for control of a wide variety of insect pests. Highly toxic to bees. Extremely toxic to aquatic organisms. (Group 3A, REI 12h)

Mycotrol ESO (Beauveria bassiana): A fungus that kills adults or larvae by penetrating the cuticle and growing inside the insect. Target pest must contact pesticide directly or be on treated foliage. Registered for use in field and greenhouse on most vegetable crops for control of grasshoppers, aphids, whiteflies, thrips, leafhopper, caterpillars and leaf-feeding beetles, including Colorado potato beetle. Approved for organic production by the Washington State Department of Agriculture. (No resistance classification, REI 4h) 

Nealta Miticide (cyflumetofen): A beta-ketonitrile contact miticide labeled for use on tomatoes to control tertanychid mites only. (Group 25, REI 12h)

NeemixOG (azadirachtin): See Azatin for more information.

Nemasys (Steinernema feltiae): A biological control for thrips in greenhouse operations and other uses. Entomopathogenic nematodes must be refrigerated and cannot be frozen. (Group un, No REI).

Nemasys G (Heterorhabditis bacteriophora): A biological control for white grubs and other uses. Entomopathogenic nematodes must be refrigerated and cannot be frozen. (Group un, No REI).

Nemasys L (Steinernema kraussei): A biological control for black vine weevil and other uses. Entomopathogenic nematodes must be refrigerated and cannot be frozen. (Group un, No REI).

Nudrin* (methomyl): See Lannate for more information.

Nufarm Abamectin* (abamectin): See Agri-Mek for more information.

Nuprid (imidacloprid): See Admire for more information.

Oberon (spiromesifen): A selective tetronic acid derivative insecticide and miticide with translaminar activity. Works on contact and by ingestion to kill juvenile stages of target pests, particularly whitefly pupae. Registered as a foliar spray on sweet corn, cucurbits, fruiting vegetables, leafy greens, brassicas, and tubers and corms for control of aphids, whiteflies, psyllids, and mites. Not for use in greenhouses. (Group 23, REI 12h)

Onyx* (bifenthrin): See Brigade for more information.

Ornazin (azadirachtin): See Azatin for more information.

Orthene (acephate): A systemic organophosphate insecticide that targets nerve and muscle tissue on contact. Registered for use as a foliar spray for beans, Brussels sprouts, cauliflower, celery, crisphead lettuce, mint and peppers to control caterpillars and other pests. Highly toxic to bees. (Group 1B, REI 24h)

Pasada (imidacloprid): See Admire for more information.

Permethrin* (permethrin): See Pounce for more information.

PermaStar* (permethrin): See Pounce for more information.

Perm-Up* (permethrin): See Pounce for more information.

PFR-97OG (Isaria fumosorosea Apopka Strain 97): A naturally-occurring fungus that penetrates the cuticle of insect pests. Labeled for foliar and soil applications on greenhouse and field-grown vegetable crops to control a variety of insect pests. (No resistance classification, REI 4h)

Piston (chlorfenapyr): See Pylon for more information.

Platinum (thiamethoxam): A selective systemic neonicotinoid. Works through ingestion, targeting nerve and muscle tissue. Registered as a soil treatment for brassicas, cucurbits, fruiting vegetables, leafy greens, roots, tubers, and corms for control of aphids, flea beetles, whiteflies, and other pests. Not for use in greenhouses or on plants grown for use as transplants. Highly toxic to bees. (Group 4A, REI 12h)

Portal (fenpyroximate): An insecticide and miticide that works on contact to disrupt pest species’ ability to generate energy. Registered for use as a foliar spray on corn, cucumbers, fruiting vegetables, melons, potatoes, and snap beans for control of leafhoppers, mites, psyllids and whiteflies. Good rotational product to alternate with other chemistries. Low toxicity to bees and mammals. Extremely toxic to aquatic organisms. (Group 21A, REI 12h)

Pounce* (permethrin): A broad-spectrum pyrethroid insecticide that works as a nerve toxin. Registered for use as a foliar spray on a variety of crops for control of caterpillars and other pests. Extremely toxic to aquatic organisms and highly toxic to bees. (Group 3A, REI 12h)

PQZ (pyrifluquinazon): Selective insecticide for use for various sucking (sap-feeding) insects such as whiteflies, thrips, aphids, mealybugs and leafhoppers on vegetable and fruit crops. (Group 9B, REI 12h)

PreferalOG (Isaria fumosorosea Apopka strain 97): See PFR-97 for more information.

Prev-AM Ultra (sodium tetraborohydrate decahydrate): An insecticide, miticide and fungicide that utilizes borax to desiccate soft-bodied insects. Registered for use as a foliar spray on a range of crops to control aphids, caterpillars, thrips, whiteflies, and other pests. Also for control of downy mildew, powdery mildew, and late blight. (Group 25, REI 12h)

Prey (imidacloprid): See Admire for more information.

Proclaim* (emamectin benzoate): A selective avermectin insecticide, derived from a metabolite of the bacterium, Streptomyces avermitilis. Works through ingestion to target nerve and muscle tissue of lepidopteran larvae. Registered for use as a foliar spray with translaminar activity on brassicas, fruiting vegetables (except cucurbits), and leafy vegetables to control caterpillars. Not for use in greenhouses or on plants grown for use as transplants. Highly toxic to bees. (Group 6, REI 12h)

Prokil Cryolite (cryolite): A high rate per acre, fluorine-based insecticide that works as a stomach poison. Labeled for use as a foliar spray on broccoli, Brussels sprouts and cauliflower, melons, squash, and peppers to control several insect pests including flea beetles and some caterpillars. (Group un, REI 12h)

Province II (lambda-cyhalothrin): See Warrior for more information.

PureSpray Green (mineral oil): See Suff-Oil for more information.

PyganicOG (pyrethrins): A broad-spectrum botanical pyrethrum. A fast-acting contact toxin with a short residual, it decays rapidly in sunlight and soils. Registered for use in field and greenhouse on a variety of crops to kill a wide range of insects. Highly toxic to bees. (Group 3A, REI 12h)

Pylon Miticide (chlorfenapyr): A pyrrole insecticide and miticide which works on contact and via ingestion, causing the pest to be unable to generate energy. Has translaminar activity. Registered for use as a foliar spray in greenhouses on tomatoes, eggplant, and peppers, for control of caterpillars, mites, and thrips. (Group 13, REI 12h)

Pyrethrum TR (pyrethrins + piperonyl butoxide): See Pyronyl Crop Spray for more information. 

Pyronyl Crop Spray (pyrethrins + piperonyl butoxide): A broad-spectrum botanical pyrethrum mixed with a synergist (piperonyl butoxide) to improve efficacy. See Pyganic for more information.

Quasar (acetamiprid): See Assail for more information.

Radiant (spinetoram): A nerve and stomach poison derived from the bacterium Saccharopolyspora spinosa; works on contact and by ingestion and has translaminar activity. Registered for use as a foliar spray on asparagus, brassicas, corn, cucurbits, herbs, legumes, and bulb, fruiting, leafy, root, and tuber vegetables for control or suppression of caterpillars, leafminers, psyllids, thrips, and certain beetles. Labeled for suppression of cabbage root maggot in leafy brassicas. Also has 2(ee) label for control of spotted-wing drosophila on fruiting vegetables. Toxic to bees for 3 hours following treatment. (Group 5, REI 4h)

Reaper* (abamectin): See Agri-Mek for more information.

Regent* (fipronil): A chloride channel antagonist that targets nerve and muscle tissue. Registered for in-furrow use on potatoes to control wireworms only. (Group 2B, REI 0h)

Requiem (Chenopodium ambrosioides extract): A contact insecticide and miticide derived from the herb Chenopodium ambrosioides; works on contact. Registered for use as a foliar spray on brassicas, bulbs, cucurbits, fruiting, leafy, root, tuber, and corm vegetables to control leafminers, thrips, and whiteflies. Low impact on beneficials. (No resistance classification, REI 4h)

Respect* (zeta-cypermethrin): See Mustang for more information.

ReTurn (oxamyl): See Vydate for more information.

Rimon (novaluron): An insect growth regulator that works through contact or via ingestion on immature stages to disrupt cuticle formation during molt, causing death. Best used on early stages, no activity against adult pests. Registered for use as a foliar spray on beans, cucurbits, fruiting vegetables, brassicas, sweet corn, potatoes, and sweet potatoes for control of a wide range of pests. Not for use in greenhouses, except on tomatoes. Low impact on beneficials. (Group 15, REI 12h)

Safari (dinotefuran): A systemic neonicotinoid that targets insect nerve and muscle tissue. Registered for use as a foliar spray on a variety of vegetable transplants grown in enclosed structures for control of aphids, leafminers, mealybugs, thrips, and whiteflies. Highly toxic to bees. (Group 4A, REI 12h)

Sanmite (pyridaben): An insecticide and acaricide for use in greenhouse cucumbers and tomatoes. (Group 21A, REI 12h).

Scorpion (dinotefuran): See Venom for more information.

SeduceOG (spinosad):  An insecticidal bait derived from the soil bacterium Saccharopolyspora spinosa; acts as a nerve and stomach poison. Attracts and kills insects feeding on or near the base of plants. Registered as a soil treatment on a variety of crops to control a wide range of pests. (Group 5, REI 4h)

Sefina (afidopyropen): See Versys. Labeled for use on cucurbits and other frutiing vegetables.

Sevin (carbaryl): A carbamate that targets nerve and muscle tissue primarily through contact activity. Registered for use as a foliar spray on asparagus, brassicas, cucurbits, legumes, roots, tubers, and fruiting and leafy vegetables to control a range of insect pests. For cutworms, granular formulation or liquid formulation may be used on some crops. Harmful to beneficials, highly toxic to bees, and extremely toxic to aquatic invertebrates. Note: long REI before detasseling corn. (Group 1A, REI 12h, 24h for sweet corn, 21 days before detasseling corn)

Shuttle O (acequinocyl): See Kanemite for more information.

Silencer* (lambda-cyhalothrin): See Warrior for more information.

Sivanto (flupyradifurone): A broad-spectrum insecticide in a new class of chemistries, the Butenolides. Acropetally systemic, and translaminar. Labeled for foliar applications in brassicas, cucurbits, fruiting, leafy, legume, root, and tuberous and corm vegetables for control of aphids, leafhoppers, whitefly, and in some crops, Colorado potato beetle, squash bugs, and psyllids. Also labeled for soil applications in cucurbits, fruiting vegetables, and leafy vegetables for control of aphids, leafhoppers, and whitefly. (Group 4D, REI 4h)

Skyraider* (bifenthrin + imidacloprid): See Brigade and Admire for more information.

SluggoOG (iron phosphate): A snail and slug bait and molluscicide. Disrupts feeding immediately and produces mortality in 3-6 days. Registered for use as a soil treatment to be scattered on moist soil around the perimeter of fields or banded in rows. May also be used in and around greenhouses; scatter around perimeter of greenhouse, or in and around pots. Low-risk material exempt from tolerances on food commodities. (No resistance classification, REI 0h)

SluggoOG Plus (iron phosphate + spinosad): See Sluggo + Entrust for more information.

Sniper* (bifenthrin): See Brigade for more information.

Steed* (bifenthrin + zeta-cypermethrin): See Brigade and Mustang for more information.

Suffoil-XOG (mineral oil): A paraffinic oil insecticide, miticide and fungicide. Kills eggs, larvae and nymphs of insects and mites and adults of soft-bodied insects through suffocation. Registered for use as a foliar spray on a variety of crops to control a wide range of pests. Safe for use in greenhouses. (No resistance classification, REI 4h)

SurroundOG (kaolin): A naturally-derived clay protectant and insect repellent. Registered for use as a foliar spray on a variety of crops to repel certain beetles, leafhoppers, thrips, and other pests. (No resistance classification, REI 4h)

Swagger* (imidacloprid + binfenthrin): See Admire and Brigade for more information.

Talstar Nursery* (bifenthrin): For greenhouse herbs only. See Brigade for more information.

Talus (buprofezin): An insect growth regulator that disrupts insect cuticle formation during molting through contact, ingestion, and vapor activity. Suppresses oviposition of adults and reduces viability of eggs. Mortality takes 3-7 days.  Registered as a foliar spray on greenhouse tomatoes to control leafhoppers, mealybugs, planthoppers, and whiteflies. Long residual (up to 28 days). (Group 16, REI 12h)

Tempest* (bifenthrin + imidacloprid): See Brigade and Admire for more information.

Tersus (pyrethrins): See Pyganic for more information.

Thimet* (phorate): An organophosphate that is taken up by plant roots and acts systemically to target insect nerve and muscle tissue.  Registered as a soil treatment in beans, corn, and potatoes for control of a range of pests. Highly toxic to bees. (Group 1B, REI 48h)

Timectin* (abamectin): See Agri-Mek for more information. 

Tombstone* (beta-cyfluthrin): See Baythroid for more information.

Torac (tolfenpyrad): A mitochondrial electron transport inhibitor that acts on contact. Registered for use as a foliar spray on leafy vegetables to control leafhoppers, aphids, flea beetle, and thrips.  Highly toxic to bees. (Group 21A insecticide, Group 39 fungicide, REI 12h)

Tracer (spinosad): For control of caterpillars, leafminers, thrips, and other pests on corn and soybeans only. See Entrust for more information.

Transform (sulfoxaflor): Sole member of a new resistance classification subgroup, active against sap-feeding pests. Labeled for use as a foliar spray on potatoes and root and tuber vegetables to control aphids, leafhoppers, potato psyllids and whitefly, and on succulent and dry beans to control aphids and plant bugs. Can be used as a rotational tool. Highly toxic to bees. (Group 4C, REI 24h). Note: After being cancelled in 2015, sulfoxaflor registrations have been reinstated by the EPA under limited-use restrictions.

TriActOG (neem oil): For use on vegetable transplants. See Azatin for more information. 

TridentOG (Bacillus thuringiensis subsp. tenebrionis strain SA-10): A bacterium-derived larvicide, labeled for control of Colorado potato beetle on potatoes, tomatoes, and eggplant. Must be ingested to be effective, so thorough plant coverage is essential. Most effective on young larvae in the first or second instar, or up to 1/4" in length. Apply as soon as eggs begin to hatch. After ingestion, larvae will stop feeding within a few hours and die within 2-4 days. Use of an adjuvant may improve efficacy, but avoid mixing with silicone-based surfactants. (Group 11, REI 4h) Note: Due to issues with formulation and shipping, Trident is not currently available.

Trigard (cyromazine): An insect growth regulator that acts by ingestion. Registered for use as a foliar spray on beans, brassicas, bulbs, cucurbits, leafy greens, peppers, and tomatoes for control of leafminers. Also labeled for Colorado potato beetle control in potatoes and suppression in tomatoes. (Group 17, REI 12h)

TrilogyOG (clarified hydrophobic extract of neem oil): A broad-spectrum miticide and fungicide, containing oil extracted from seeds of the neem tree. Mite control depends on direct contact and requires thorough coverage. Registered as a foliar spray on a variety of crops for a range of pests. (No resistance classification, REI 4h) 

VenerateOG (Heat-killed Burkholderia spp.): A biological insecticide containing killed cells and fermentation solids of Burkholderia spp. Works by contact and ingestion to disrupt insect exoskeletons and interfere with molting. Registered for use as a foliar spray on most vegetables to control foliar feeding and plant-sucking pests. (No resistance classification, REI 4h)

Venom (dinotefuran):  A neonicotinoid that targets insect nerve and muscle tissue. Acts by contact and ingestion. Becomes systemic when applied to soil, and has translaminar activity when applied to foliage. Registered for use as a foliar spray or soil treatment on cucurbits, fruiting vegetables, brassicas, leafy greens, and potatoes to control sucking and chewing insects. Highly toxic to bees. (Group 4A, REI 12h)

Verimark (cyantraniliprole): A systemic diamide that works by ingestion of treated plant material. Labeled for use in soil applications on brassicas, cucurbits, fruiting, leafy, and tuberous and corm vegetables to control sucking and chewing insects, including caterpillars, aphids, flea beetles, leafminers, thrips, and cabbage maggot. Also labeled for control of seedcorn maggot in cucurbits. May also be used as a potato seed piece treatment. Highly toxic to bees. (Group 28, REI 4h)

Versys (afidopyropen): Chordotonal organ modulator acts to stop feeding immediately. Labeled for use on brassica head and stem vegetables, leaf petiole vegetables, leafy vegetables, pome fruit, and stone fruit. (Group 9D, REI 12 h)

Vetica (flubendiamide + buprofezin): Note: All flubendiamide registrations were canceled by the EPA in 2016. Growers may use up existing stock. See Belt and Talus for more information.

Voliam Flexi (chlorantraniliprole + thiamethoxam): See Coragen and Actara for more information on active ingredients in this product.

Vydate* (oxamyl): A systemic carbamate insecticide and nematicide that is taken up by plant roots and acts on contact or by ingestion to target nerve and muscle tissue. Registered for use as a foliar spray or soil treatment on carrots, some cucurbits, eggplant, peppers, tomatoes, and sweet potatoes for control of nematodes and several insect pests. Labeled for control of brown marmorated stink bug in pepper and tomato. Highly toxic to bees, and extremely toxic to birds, fish, and mammals. (Group 1A, REI 48h)

Warrior* (lambda-cyhalothrin): A broad-spectrum pyrethroid insecticide that targets nerve and muscle tissue. Registered for use as a foliar spray on brassicas, cucurbits, sweet corn, fruiting vegetables, legumes, lettuce, bulb onions, garlic, and tuberous and corm vegetables to control a range of pests. May be applied before, during, or after planting for cutworm control. Highly toxic to bees, and extremely toxic to aquatic organisms. (Group 3, REI 24h)

Wrangler (imidacloprid): See Admire for more information.

XenTariOG (Bacillus thuringiensis subsp. aizawai): A derivative of the bacterium Bacillus thuringiensis subsp. aizawai. Works via ingestion, stopping feeding within an hour and inducing mortality within 3 days. Registered for use in field or greenhouse as a foliar spray on most vegetables for the control of caterpillars. May be especially useful for control of diamondback moth larvae that are resistant to Bt kurstaki or other products. Toxic to green lacewing and predatory mite (Metaseiulus occidentalis) (Group 11, REI 4h)

Xpedient* (bifenthrin): See Capture for more information.

Zeal (etoxazole): A mite growth regulator that works as an ovicide and larvicide. Registered for use as a foliar spray on cucurbits, mint, eggplant, and peppers to control mites. (Group 10B, REI 12h)

Zoro* (abamectin): See Agri-Mek for more information.

Zylo (methoxyfenozide): See Intrepid for more information.

Zyrate (esfenvalerate): See Asana for more information.

Table 26: Information about Insecticides and Miticides

Pesticides listed in bold were used as examples; their labels and MSDS were consulted for the data given in this table. This information may vary slightly for the other products listed. No preference is indicated by this distinction.

All tolerances for chlorpyrifos in food crops were revoked in 2022, therefore products containing chlorpyrifos (e.g. Lorsban) cannot be applied to any food crop and growers CAN NOT use up existing stock.

The symbol * indicates a federally restricted use pesticide. Unmarked active ingredients may have state restrictions; always check a product's registration status in your state before using.

The symbol OG indicates a pesticide that has been listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production.

Mixtures are listed under all active ingredients and indicated with an (M). 

When tank mixing pesticides, mix in the proper order. The order is Wettable Powders (WP), Water Dispersible Granules (WDG), Flowables (F) (DF) (SC), Water-dispersible liquids (AS), Emulsifiable Concentrates (EC), and Solutions (S). Always follow the pesticide label when using adjuvants such as spreader stickers, surfactants, etc.

Active Ingredient

Trade Name and Formulations

Signal Word

Resistance Group (IRAC¹ code)

Dermal LD50

Oral LD50

Toxicity to bees

abamectin*

Abacus; Abamex; Agri-Mek SC; Athena (M); Clinch Ant Bait; Nufarm Abamectin 0.15EC; Reaper 0.15EC, ClearForm; Tide Timectin 0.15EC; Zoro Miticide/Insecticide

W

6

>2,000

310

H

acephate

Acephate 90 Prill, 90 WDG, 90 WSP; Acephate 97 UP; Orthene 97

C

1B

>2,000

688

H

acequinocyl

Kanemite 15SC; Shuttle O

C

20B

>2,000

>5,000

L

acetamiprid

Assail 30SG, 70WP

C

4A

>2,000

805

M

alpha-cypermethrin* Fastac EC D 3A >5,000 >210 - <1,050 H
afidopyropen Inscalis, Sefina, Versys C 9D >2,000 1,320-6,690 L

azadirachtin

Amazin Plus 1.2%MEOG; Aza-DirectOG; AzaGuardOG, Azatin OOG; XL; Azatrol ECOG; AzeraOG(M); Ecozin Plus 1.2%MEOG; Molt-XOG; Neemix 4.5OG, Ornazin 3%EC

C

un

>2,000

>5,000

L

Bacillus thuringiensis subsp. aizawi

XenTariOG

C

11

>2,000

>5,000

L

Bacillus thuringiensis subsp. isrealensis

Gnatrol WDGOG

C

11

>5,000

>5,000

L

Bacillus thuringiensis subsp. kurstaki

CoStarOG; DeliverOG; Dipel ES, Dipel DFOG; Javelin WGOG

C

11

>2,020

>5,000

L

Bacillus thuringiensis subsp. tenebrionis strain SA-10 TridentOG (currently off the market due to formulation and shipping issues) C N/A -- -- M

Beauveria bassiana

Botanigard ES, 22WP; Mycotrol ESO

C

M

--

--

L

beta-cyfluthrin*

Aztec 2.1G (M), 4.67G (M); Baythroid XL; Defcon 2.1G (M); Leverage 360 (M); Tombstone, Helios

W

3

>2,000

647

H

bifenazate

Acramite 50WS; Floramite SC

C

un

>5,000

>5,000

M

bifenthrin*

Athena (M); Bifenture EC, 10DF; Brigade 2EC, WSB; Brigadier (M); Capture LFR; Discipline 2EC; Empower 2 (M); Fanfare ES; Hero (M), EW (M); Match-Up (M); Skyraider (M); Sniper, Helios, LFR; Steed (M); Swagger (M, EPA rated D); Talstar Nursery; Tempest (M); Xpedient Plus

W

3A

nil

262

H

buprofezin

Talus 70DF; Vetica (M)

C

16

>2,000

>5,000

L

Burkholderia spp. (heat killed) Strain A396 and spent fermentation media Venerate XCOG C N/A >5,050 >5,000 M

capsicum oleoresin extract

Captiva (M)

C

N/A

>2,000

>5,000

L

carbaryl

Carbaryl 4L; Sevin XLR Plus, 4F

C

1A

>4,000

699

H

Chenopodium ambrosioides extract

Requiem EC

C

--

>2,020

>5,000

L

chlorantraniliprole

Besiege* (M); Coragen, Durivo (M); Voliam Flexi (M)

C

28

>5,000

>5,000

L

chlorfenaspyr

Pylon Miticide

C

13

>2,000

560

M

Chromobacterium subtsugae

GrandevoOG

C

--

>5,000

>5,000

M

cinnamon oil

Ecotrol G2OG (M)

C

N/A

--

--

L

Clarified hydrophobic extract of neem oil

Triact 70OG; TrilogyOG

C

--

>2,000

>5,000

M

clothianidin

Belay, 50WDG

C

4A

>5,000

>3,900

H

clove oil

Ecotrol G2OG (M)

C

N/A

--

--

L

cryolite

Prokil Cryolite 96

C

un

--

--

L

cyantraniliprole

Exirel; Verimark

C

28

>5,000

>5,000

H

cyclaniliprole Harvanta C 28 >2,000 >2,000 H

cyflumetofen

Nealta Miticide

C

25

>5,000

>2,000

L

cyromazine

Trigard

C

17

>2,010

4,460

L

deltamethrin*

Delta Gold

D

3A

>2,000

42.9

H

diazinon*

Diazinon AG500, 50W, AG600 WBC

C

1B

>2,000

787

H

diflubenzuron*

Dimilin 25W

C

15

>20,000

>10,000

L

dimethoate

Dimate 4EC; Dimethoate 4EC, 400

W

1B

1,000

60

H

dinotefuran

Safari 20SG; Scorpion 35SL; Venom

C

4A

>2,000

>2,000

H

emamectin benzoate*

Proclaim

C

6

>2,000

1,516

H

esfenvalerate*

Asana XL; Zyrate (M)

W

3

>2,000

458

H

ethoprop*

Mocap 15G, EC, 15G Lock n Load

D

1B

166

15.9

H

etoxazole

Zeal, WDG

C

10B

>5,000

>5,000

L

fenpropathrin*

Danitol 2.4EC

W

3

>500 - <5,000

>50 - <500

H

fenpyroximate

Akari 5SC; Portal XLO

W

21A

>2,000

810

L

fipronil*

Regent 4SC

W

2B

382

336

H

flonicamid

Beleaf 50SG

C

9C

>2,000

>2,000

L

flupyradifurone Sivanto 200SL C 4D >2,000 >2,000 L

gamma-cyhalothrin*

Bolton (M); Cobalt (M); Consero (M); Declare

C

3A

>5,000

>2,250

H

garlic oil

Captiva (M)

C

N/A

>2,000

>5,000

L

geraniol Ecotrol PlusOG (M) C N/A -- -- M

imidacloprid

Admire Pro; Advise Four; Alias 4F; AmTide Imidacloprid 2F, 4F; Brigadier (M); Couraze 2F, 4; Leverage 360 (M); Macho 2.0FL, 4.0FL; Mallet 75WSP; Marathon 1% Granular, 60WP, II; Midash Forte; Montana 2F, 4F; Nuprid 2SC, 4F Max; Pasada 1.6F; Skyraider* (M); Swagger* (M, EPA rated D); Tempest* (M); Wrangler

C

4A

>2,000

4,143

H

indoxacarb

Avaunt

C

22

>5,000

687

H

insecticidal soap

See potassium salts of fatty acids

 

 

 

 

 

iron phosphate

Sluggo: Slug and Snail BaitOG

C

N/A

>5,000

>5,000

L

Isaria fumosorosea Apopka Strain 97 (formerly Paecilomyces fumosoroseus)

PFR-97 20% WDGOG , PreferalOG

C

M

--

--

M

kaolin

Surround WPOG

C

N/A

--

>5,000

L

lambda-cyhalothrin*

Besiege (M); Cobalt Advanced (M); Endigo ZC (M); Grizzly Too; Lambda-cy EC; Lambda-T2; Silencer 1EC; Warrior II with Zeon

W

3A

>2,000

180

H

malathion

Fyfanon ULV AG; Malathion 57EC, 5, 5EC, 8F, 8 Aquamul

W

1B

>2,000

550

H

metaldehyde

Deadline M-Ps, Bullets, GTs

C

N/A

>5,050

>5,000

L

Metarhizium anisopliae Strain F52

Met52 EC

C

N/A

>5,000

--

L

methomyl*

Lannate LV, SP; Nudrin LV, SP

D

1A

>2,000

49

H

methoxyfenozide

Intrepid 2F

C

18

>2,000

>5,000

L

Mineral (or paraffinic, or petroleum) oil

 

Damoil; Organic JMS Stylet OilOG, JMS Stylet Oil, Mite-E-Oil; Suffoil-XOG

C

M

>2,000

>5,000

L

neem oil

See clarified hydrophobic extract of neem oil

 

 

 

 

 

novaluron

Rimon 0.83EC

W

15

>2,000

>5,000

L

oxamyl*

Vydate L, C-LV

D

1A

>5,000

9

H

peppermint oil

Ecotrol PlusOG (M)

C

N/A

--

--

M

permethrin*

Ambush 25W; Arctic 3.2EC; Permethrin 3.2AG; Perm-up 3.2EC; Pounce 25WP, 1.5G

C

3A

>2,000

1,100

H

phorate*

Thimet 20G Lock n Load, 20G Smartbox, 20G EZ Load

D

1B

86

5

M

phosmet

Imidan 70W

W

1B

>2,000

258

H

potassium salts of fatty acids

DES-XOG; M-PedeOG

W

M

--

--

L

pymetrozine

Fulfill

C

9B

>2,000

>5,000

L

pyrethrins

AzeraOG (M); Evergreen EC 60-6 (M); Pyganic EC1.4OG, Pyganic EC5.0IIOG; Pyrethrum TR (M); Pyronyl Crop Spray (M); Tersus

C

3A

>2,000

>2,000

M

pyriproxyfen

Distance IGR; Esteem 0.86EC; Knack IGR

C

7D

>2,000

3,773

L

rosemary oil

Ecotrol PlusOG (M)

C

N/A

--

--

M

sodium tetraborohydrate

Prev-AM Ultra

W

8D

>2,000

>5,000

L

soybean oil

Captiva (M); Golden Pest Spray OilOG

C

N/A

L

spinetoram

Radiant SC

C

5

>5,000

<5,000

M

spinosad

Blackhawk; Consero* (M); EntrustOG; Entrust SCOG; GF-120 NaturalyteOG; SeduceOG; Tracer

C

5

>5,000

>5,000

M

spiromesifen

Oberon 2SC, 4SC

C

23

--

>2,000

M

spirotetramat

Kontos Greenhouse and Nursery; Movento

C

23

--

>2,000

M

sulfoxaflor Closer; Transform D 4C >5,000 >2,000 H

sulfur

Bonide Garden Dust; Microfine sulfurOG; Microthiol DisperssOG

C

M2

2,000

>2,000

L

tebufenozide

Confirm 2F

C

18

>5,000

>5,000

L

tebupirimfos*

Aztec 2.1G (M), 4.67G (M); Defcon 2.1G (M)

W

3A, 1B

>2,000

132

L

tefluthrin*

Force CS, 3G, 3G Smartbox

W

3A

2,000 – 5,000

174

H

terbufos*

Counter 20G Smartbox

D

1B

71

8

M

thiamethoxam

Actara 25WDG; Cruiser 5FS, Maxx Potato (M), Vibrance Quattro (M); Durivo (M); Endigo* ZC (M); Platinum, 75SG; Voliam Flexi (M)

C

4A

>2,000

>5,000

H

thyme oil

Ecotrol G2OG (M)

C

N/A

--

--

L

tolfenpyrad

Torac

W

21A

>2,000

83

H

zeta-cypermethrin*

Hero (M), EW (M); Holster, Mustang, MAXX; Respect EC; Stallion (M); Steed (M)

W

3A

>2,000

234

H

1= Insecticide Resistance Action Committee

Weed Management

Weeds compete with crops for water, light, and nutrients thereby reducing crop yield and quality.  Competitive effects of weeds are density dependent, with increasing weed density causing increasing crop yield loss. The magnitude of loss varies based on the crop and weed species present and the timing of competitive interactions. Carrot, beet and Alliums, for example, are small-seeded, slow to emerge, and are poorly competitive early in the growing season. Larger-seeded crops like pea, bean, and corn, tubers (potato), or transplanted crops start with a significant initial size advantage over germinating weeds. A first principle of weed management is to establish this size advantage, and then maintain it with early weeding or mulching to reduce the density of competition weeds. To this end, successful weed management requires good foundational agronomic and horticultural practices regarding seedbed preparation, fertility and moisture management, timing and density of planting, choice of variety, as well as necessary early management of insect pests and plant pathogens. Remember, in plant competition, “The Big Get Bigger!”  

Weed Biology and Ecology

Weed identification is now easier than ever, with apps like “Picture This” getting better every year. While apps still perform poorly in identifying grasses and weed seedlings, recognizing your mature weedy flora is a great place to start. Weeds of the Northeast by Uva, Neal and DiTomaso is another useful reference for weed identification.

Weedy plant species often share certain traits or characteristics that contribute to their success as early the early colonists of disturbed sites, which is after all, the ecological job or “niche” of a weed. Fundamental weedy traits include rapid growth, high amount of seed production, and most notably, seed/bud dormancy to ensure offspring germinate and attempt to grow over several future years, an impressive bet-hedging strategy. Weedy species are also known for their “plasticity,” in other words, genotypic flexibility whereby an individual may exhibit different morphology in response to its environment (e.g., bushy growth in full sun but erect growth in a dense crop). 

Annual plants complete their life cycle in one year: seeds germinate, seedlings grow to maturity, flower, and reproduce all within a single growing season. Winter annuals germinate in late summer or fall, overwinter, and set seed the following spring. Summer annuals germinate in spring or early summer and set seed before fall, often in response to shorter days. Timing of germination and thus emergence is affected by species specific dormancy characteristics and environmental conditions including light quality (e.g., affecting phytochrome), temperature, moisture, gas exchange, nitrate among many other factors. These in turn are dramatically affected by soil disturbance (tillage or cultivation). Thus, it should be no surprise that annual weeds dominate the weedy flora of vegetable farms that rely on soil disturbance for residue management, seedbed preparation, amendment incorporation and weed control. 

Weed seedbanks vary widely across farms. The seedbank refers to weed seeds on the soil surface or buried in the soil. Generally, seedbanks are larger on organic farms compared to farms using herbicides. Larger seedbanks result in a higher density of weed seedlings, or greater “weed pressure” as described by some farmers. The “bank” metaphor is useful in thinking about management, specifically the aim to reduce “credits” to the bank, i.e., avoid or reduce weed seed rain, while encouraging “debits” or losses. A common misperception is that weed seeds last “forever” in the soil, so “why bother to manage the seedbank?” While it is true that a seed may occasionally last many years, perhaps decades, by far, most seeds germinate or die in the first year. In fact, many annual weed seeds have a half-life of less than one year. In other words, 50% of the seeds produced this season will be gone in less than a year. This is true for several important weeds in our region, including, redroot pigweed, common lambsquarters, hairy galinsoga, yellow foxtail, and crabgrasses.

Vegetable farmers are fortunate in having many options related to weed seedbank management. Consider a field that will be used for a sequence of short season crops like radish or leafy greens. Shallow tillage for seedbed preparation in this case serves to encourage weed germination, the most important of seedbank debiting mechanisms, while harvest is completed, and residues incorporated prior to any weed maturation thus preempting seed rain.

Emergence periodicity is a useful aspect of weed biology that can be used to optimize fallowing or stale seedbed events that aim to reduce the germinable weed seedbank. Shallow tillage breaks seasonal dormancy for species ready to germinate. Thus, if targeting summer annuals, shallow tillage in June or July will encourage germination, while winter annual species will remain in the seedbank. 

Perennial weeds can live for more than one year and while most produce seed, vegetative propagation by stolons, rhizomes, or roots are generally more important.  Tillage operations often drag perennial weed fragments from sod headlands or farm roads into vegetable fields. Shallow tillage around field margins throughout the growing season can establish a fallow zone to avoid this dispersal from tillage.

Monitoring weeds is an important but often neglected part of a weed management plan.  Weed maps of field areas are extremely helpful in planning weed control strategies. A weed map can illustrate problem areas so that growers can target specific problems in specific areas and help plan for future crop rotations. Over time, weed maps can show shifts in weed pressure and indicate the possible need for a strategy change. Maps can also highlight the importance of managing dispersal, e.g., avoiding tillage that drags quackgrass rhizomes from grass alleys into fields, or working around a weed patch to avoid tillage dispersal. 

Dispersal is critical to the success of weeds, but rarely a priority for management. It is widely thought that weed seeds are blowing in from neighbors, hitching rides from birds or mammals, or washing in with irrigation or surface waters. These are important dispersal mechanisms, but they are rare events generally moving only a very small fraction of a batch of seeds. In fact, well over half of most seeds are dispersed right around the base of the mother plant, and most remaining seeds not much further. In a natural setting, these seeds would be very crowded, with intense competition among the weeds when a cohort germinates the following year. In a farmed system, however, tillage events serve to disperse the seeds, spreading them out to the benefit of the weed. These local dispersal factors drive the patch dynamics that will be evident in your weed maps, with dense areas where reproduction was high, lower density radiating from the patch where tillage moved seeds, and then many other locations where weeds may be absent. 
 

Physical Weed Control

Physical weed control refers to actions that remove or kill weed seedlings, aiming to reduce weed density and thus maximize crop yield and quality. In vegetable crops this often includes hand weeding, which is effective, but expensive. Hand weeding time/cost is dependent on weed density, so efforts to reduce the weed seedbank and increase the efficacy of weeding tools will often improve net returns. The availability and cost of labor are key considerations, although it is common to perform some hand weeding in almost all vegetable crops.  When relying on hand labor, start weeding operations with wheel hoes that can cover a lot of area quickly not matter the weed density. Next move to long-handled hoes designed for weeding: notable favorites among veteran organic vegetable farmers include the Glaser stirrup hoe and the colinear hoe. Using tools to get as close to the crop row as possible will reduce the final hand weeding labor. When tools are used for weed removal, physical weed control is sometimes referred to as “mechanical weed control,” or simply “cultivation.”

Cultivation is an important component of weed control in vegetables, particularly when the use of herbicides and/or mulches is to be minimized or avoided. Efficacy and selectivity are important indicators of cultivation performance. Efficacy or “effectiveness,” refers to the proportion or percentage of weeds that are killed. A central problem with cultivation is that efficacy is low (60% is common) and highly variable (some places in the field efficacy is 95%, another spot only 5%). Herbicides, in contrast, have very high efficacy and very low variability; this is foundational to successful sales and few farmer complaints. Selectivity refers to killing targeted weeds, but not the crop. Cultivation tools are not particularly sophisticated in their operation, rather, selectivity is generally based on a size differential between the crop and weed. A first principle of physical weed control is to establish and then maintain the crops’ size advantage.

Cultivation strategies should start with careful seedbed preparation. Flat, firm, residue-free soil surface conditions will allow weeding tools to consistently function throughout the field. A light-weight field cultivator or soil conditioner with a rolling basket is often a good choice. While large-seeded or transplanted crops do not require a perfect seedbed for planting and stand establishment, later cultivation operations will benefit from these early season efforts to prepare a nice seedbed.

Weeds are most effectively cultivated shortly after they germinate, and crops are most sensitive to weed pressure during their early stages of growth. Thus, cultivation is most critical early in the growing season. 

Tools should be carefully adjusted, first in the shop, and then in the field after some testing. Row-crop tools should target the same number of rows that were planted, or simple fraction of this. For example, if using a one-row seeder, plan to cultivate one row at a time. If planting two or four rows, use a two or four row cultivator. Hand planting with a push seeder is generally not going to be suitable for later tractor-mounted cultivation tools.

Tools should be adjusted to work as shallow as possible to minimize movement of seeds in the seedbank and dormancy breaking. After carefully adjusting spacing, we typically place a 3/4 in. thick board under the gage wheel of parallel linkage units (depth-controlling units), and then drop tools to the floor and tighten. We also have lines marked on the shop floor indicating crop row spacing to allow precise adjustment relative to the row. Magnetic levels are handy to adjust top-linkage of three-point hitch tools, and a protractor can be used to check the angles of tools to either avoid soil movement or hill as desired.

Cultivation tools can be broadly grouped by the area of soil they disturb, with so-called “blind cultivation” working the entire tool width, and “row-crop cultivators” aiming to control weeds as close to the crop as possible.

Blind cultivation is performed after crops have been planted, over the top of them, so that both in-row and between-row areas are cultivated. To minimize crop damage, this should be done before the crop has emerged and/or once it is well rooted. Slightly deeper planting depths and slightly higher plant populations are recommended to compensate for some crop loss that may occur. Very tender crops such as leafy greens are not amenable to this technique, but a surprising array of crops are suitable for blind cultivation, including corn, cucurbits, beets, etc. depending on stage of growth and equipment used.

Tine harrows have multiple rows of flexible metal tines that cover the entire soil surface, wiggling slightly as they are pulled along, uprooting or dislodging very small weeds. They work best at relatively high speeds, and the wide span of the tool makes cultivation quick. They are rear-mounted and available in many widths. The tension on the tines can be adjusted on some units or by the pressure on the 3-point hitch on other units. Gauge wheels can be used to maintain uniform depth. Tine harrows work best in friable soils free of rocks, and when weather allows weeds to dry out on soil surface after uprooting.

Rotary Hoes have many narrowly spaced metal wheels each with about 16 curved teeth that work the surface of the soil. Used within the first few weeks of planting vigorous crops like corn or beans, they destroy weeds that have just germinated. Ground-driven, spring-loaded wheels do little damage to the crop and work well at high speeds on dry, rock-free soils with little residue. They are rear mounted, in many widths. The teeth, or spoons, lose their effectiveness if not sharp.

Between-row cultivation can be performed with varying degrees of aggressiveness, so that soil may or may not be pushed into the row to obtain some between-row weed control. Commonly used cultivation setups consist of a shank (either straight, C-, or S-shape) attached to a toolbar, with a cultivating tool (shovel, sweep, knife, hilling disc, etc.) attached to the bottom. The more curve to the shank, the more it will vibrate and flex in the soil. Trip-shanks have a release mechanism that allows the shank to pop up when it hits a rock. Shanks can be arranged on multiple toolbars to offer complete coverage between multiple rows in beds. There are many kinds of tools that can be attached to the shanks, and these should be selected to disturb only as much soil as is needed to kill the weeds present. In general, one starts the season with smaller, shallower tools to kill small weeds when the crop is small; as the season goes on, if larger weeds are present, then more aggressive tools are needed, and as the crop grows it is possible to more aggressively push soil into the row without causing damage. For example, shovels might be followed by sweeps and then hilling discs. Another strategy is to adjust the angle of cultivating tools such as hilling discs or rolling cultivators as the season goes on. Start by pulling soil away from the row when cultivating a young crop; that creates a small hill that can be pushed back into the row when the crop is a bit older to bury weeds.
In small and/or tender crops like leafy greens, shallow tools are needed that will not move soil into the row and cause damage. A side-knife (or beet-hoe) may be used to cultivate horizontally next to the crop, just below the surface.

Basket weeders are relatively high-speed, between-row cultivators good for control of small weeds in narrow rows when crop is small. The wire baskets work the soil surface and do not move soil into the row, but they don't work well in crusted or rocky soil. The front set of baskets are ground driven, and they turn the rear set of baskets a bit faster via a chain and gearing, causing scuffing of the soil. These are available in 2-6-row units that can be rear or belly-mounted.

Finger weeders consist of steel cone wheels that are ground-driven by spike tines on the bottom, with rubber fingers on the perimeter.  The rubber fingers work the soil just below the surface, uprooting small weeds located very close to the crop. Finger weeders work best for control of small weeds in dry, friable soil with few rocks or residues. Clay soils may stick to fingers.

Spring-hoe, torsion weeders, and spyder weeders are flexible blades and square metal stock that disturb soil around base of plants, and ground-driven spyder wheels with staggered teeth in an uneven pattern that break clods and throws soil into row, or pull it away, depending on the angle. These can be toolbar-mounted, either under the belly or in the rear. They can be used together, separately, or in conjunction with other cultivators.

Rolling cultivators have gangs of soil-driven 'spider wheels' that mount independently on a toolbar. The angle that they work the soil, and thus their aggressiveness, is usually adjustable. The number of gangs grouped together determines cultivator width, and these are usually rear-mounted, but pairs of gangs may be belly mounted to work a row or two. Soil can be thrown into row to bury small weeds or to form hills, depending on angle of the gangs. This is a relatively heavy, aggressive tool.

Reigi weeders require a rear operator who steers a pair of rotating horizontal wheels in and out of the crop row. The wheels are turned by a PTO-driven belt, and they have stiff tines on them that root out weeds. The wheels come in several sizes useful for various row spacings, and the units come in 1 or 2-row models. These are very effective for killing weeds in and next to the row in widely spaced crops like pumpkins, first-year strawberries, or sweet corn with a lot of skips.

Flame weeders can be used to kill weeds before planting without causing soil disturbance that brings up new weed seeds, after the crop has been planted (but before it emerges), inter-row weeding, and for stale seed bed preparation. Flame weeding, also known as thermal weeding or flame cultivation, exposes plants to brief periods of high temperature that causes the water in the plant tissue to expand rapidly, rupturing plant cells and leading to tissue damage.  Plants are not burned or incinerated, but "blanched". They will not show symptoms of injury for several hours after exposure.  Some weeds, such as purslane, can tolerate high temperature, and grasses with their growing points below ground are not controlled by flaming. When weeds are moist from rain or dew, more heat (a slower tractor or walking speed) will be necessary.

Like with contact herbicides, flaming kills weeds without soil disturbance, it is ideal for stale seedbeds. Once broadleaf weeds reach the three-leaf stage, they should be flamed to prevent them from growing too large. For longer lasting weed control, apply the final flaming as late as possible prior to crop emergence after seeding or just prior to transplanting.

Hand-held propane torches are commonly used to flame single rows at a time, but multi-row bed-flamers and tractor-mounted flamer kits are also available. Larger units require greater attention to safety during construction and operation. Safety is a big issue with flaming. Consult with a gas professional if constructing your own flaming unit. Do not mount propane tanks intended for stationary use onto tractors. Flame against the breeze and avoid areas with dry residues or dry hedgerows. Liability concerns may hinder the use of flaming.
 

Cultural Weed Management

Cultural options include cover crops, fallowing, plant competition, mulches, soil preparation, stale beds, and crop rotation.

Cover crops alone do little to reduce overall weed populations, but shallow tillage between short cycles of cover crop growth is effective.  The tillage kills weed seedlings and encourages germination of a new “flush” of weeds that can be killed with the next disturbance.  Through these cycles, the objective is to encourage weed seed germination but not to allow further weed seed production.  A dense stand will provide weeds suppression while it is growing which is important for a season-long cover crop in which weeds may mature and set seed.  Cover crops can also slow the warm-up of soil and provide shade, both helping to slow weed seed germination and reduce the soil seed bank over time. Perennial weeds will increase in long-term sod crops, e.g., one or more years of red clover.  

Fallowing is not planting a field with the intention to reduce weed seed populations. Repeated shallow soil disturbance will encourage weeds to germinate while subsequent events kill seedlings before they go to seed. Even in the absence of a cover crop, this strategy will reduce the weed seed bank of a field.
Plant competition is the foundation of weed management.  Remember, “the big get bigger.” Large-seeded crops and transplants have an initial size advantage over weeds.  Decreasing the space between crops will also increase soil shading.  Overall, the more rapidly a crop can cover the soil ahead of weed emergence, the more competitive that crop will be. Choose high quality seed, calibrate equipment to ensure accurate seeding rates and depth, and where possible, supply resources selectively to the crop, e.g., using fertilizers banded below/near the crop row, or drip irrigation, instead of broadcasting resources.

Mulches are often used to control weeds.  Mulches can be organic (straw, hay, grass clippings, dead cover crops) or inorganic (plastic).  Organic mulches are effective if they are thick enough to keep weeds from emerging through them (usually at least 2-3").  Downsides of organic mulches are that they can be expensive, they slow soil warm up or reduce soil temperatures, and they can harbor animal pests.  Cooler soil temperatures can be a problem in warm season crops.  It is recommended that the mulch application be delayed allowing the soil to warm up sufficiently for the crop.  Black plastic mulches will warm soil and eliminate weed pressure.  However, weeds emerging through the planting holes and between strips of plastic mulch can still reduce yields if not controlled.  Infra-Red Transmitting (IRT) mulches are less effective than black plastic for controlling weeds, and clear mulches can enhance weed growth.  Some growers plant cover crops between plastic mulch strips as "living mulch", but these cover crops can also compete with the crop.  Killing the living mulch before the crop is planted, mowing the mulch on a regular basis, or using raised beds will help to reduce but not eliminate competition.  See the section on using herbicides in combination with plastic mulches later in this section.

Proper soil preparation can influence weed emergence.  Soils which are rough and less firmly packed will yield fewer weeds than those that are more finely worked, more compacted, and more uniformly moist. However, as noted above, a well-prepared seedbed will help weeding tools function to their potential during later cultivation events.

Stale seedbed or summer fallowing is performed on fields that have been prepared for planting, either in the spring before a crop is sown, or in the summer after a spring crop but before a fall crop. The soil is then lightly disturbed on a regular basis to kill small weeds as they emerge, without bringing up new weed seeds from below the top few inches of soil. Early in the year, broadleaves will not be controlled if they have not yet emerged, so a summer fallow works better on them. Perennial weeds may be weakened but not killed. Tools that can be used for this practice include chain-drag, spring-tooth harrow, light-weight disc harrows, or tine weeders.  See additional information on the stale seedbed technique later in this section.

Crop rotation can be a tool for managing weeds. Weed species present tend to be most like crop planted. Examples include grasses in corn, winter annuals with early-planted crops, and perennial weeds with perennial crops. Rotating crops among these groups will tend to disrupt this trend.

About Herbicides

Herbicides are chemicals designed to control weeds. The use of these materials must be exact for satisfactory results. Proper rate selection, timing of application, activation, and observance of all precautions on the label must be followed to obtain optimum performance. Each herbicide controls certain weeds or families of weeds. Therefore, knowledge of the type of weed species present in the field is essential for good weed control. Once the weed problem is known, select the proper herbicide.

Herbicides can be systemic, meaning that they are absorbed and moved throughout the plant, while others are contact herbicides, meaning that they only affect the plant tissue they come into contact with. 

Preemergence Herbicides (PRE) - These herbicides are applied prior to the emergence of weeds.  In general, they work by preventing weeds that are germinating from seeds from growing, but some can also act on perennial plants that spread by rhizomes, tubers, and stolons.  Application is timed to coincide with when the target weeds are about to begin germinating.  These herbicides prevent new weeds from establishing, but most will not impact weeds that are already emerged. 

Preplant - These herbicides are applied before the crop is planted.  They can be preemergence products that are incorporated into the soil or applied to control existing vegetation. 

Postemergence Herbicides (POST) - These herbicides work on actively growing weeds.  They can be absorbed by the leaves or roots of the plants, depending on the chemical. 

Adjuvants – These products are added to a pesticide mixture to improve its effectiveness.  They include surfactants, stickers, penetrants, compatibility agents, etc.  Pesticide labels may list specific types of adjuvants that will maximize effectiveness of the pesticide.  Be sure to use the proper category of adjuvant if the manufacturer makes a specific recommendation.

When adjuvants are recommended, it is because research has shown that their addition increases efficacy of the herbicide.  If the label advocates the usage of an adjuvant, do not omit the adjuvant solely to save money.  The most common adjuvants used with herbicides are nonionic surfactants (NIS) and crop oil concentrates (COC) which can consist of petroleum, vegetable, or methylated vegetable or seed oils. They increase penetration of the herbicide through the leaf cuticle.

Herbicides and Crop Rotation Constrictions

Some herbicides can have long-lasting activity.  Many herbicides have crop rotation constrictions where they have been applied.  For example, Devrinol has a 60-day plantback interval for leafy greens. Check the label of each product for details.

Toxicity of Herbicides

The toxicity of pesticides varies by the active ingredient, concentration of active ingredient, and the formulation of the product (e.g. liquid, powder, etc.).  The toxicity of a pesticide is expressed in terms of oral (administered internally) and dermal (applied to the skin) LD50. LD50 is the dosage of poison that kills 50% of test animals (usually rats) with a single application of the pesticide product and is expressed as mg/kg of body weight. The lower the LD50 value, the more toxic the material.

The acute (short-term) toxicity of the formulated product is conveyed on label by a “signal word” stated on the front page. 

DANGER - pesticide product is highly toxic by at least one route of exposure. It may be corrosive and cause irreversible damage to the skin or eyes.  If the product is highly toxic if eaten, absorbed through the skin, or inhaled, then the word “POISON” must also be included in red letters.

WARNING - pesticide product is moderately toxic if eaten, absorbed through the skin, inhaled, or it causes moderate eye or skin irritation.

CAUTION - pesticide product is slightly toxic if eaten, absorbed through the skin, inhaled, or it causes slight eye or skin irritation.

General Principles for Safe Use

  • Know the herbicide. Read the label.
  • Check the output of sprayer frequently.
  • Replace worn nozzles. It may be necessary to replace them several times a season if the sprayer is used constantly.
  • Rinse spray equipment immediately after use. Use one sprayer for herbicides and another for insecticides and fungicides.
  • For restrictions on rates, timing and crops for which the herbicide is approved, see Table 27.
  • For degree of susceptibility of each weed to a specific herbicide, see Table 28.
  • For limitations and special requirements of the herbicide, refer to the product label (or supplemental label).

Rate Selection

Always check the label to determine the proper rate to apply. For most soil-applied herbicides, knowledge of the type of soil and the percentage organic matter usually determines the rate. Generally, the more clay and/or organic matter present in the soil, the higher the herbicide rate necessary for good weed control. For postemergence herbicides, the type of weed, as well as its size, will usually determine the rate.

Incorporation of Herbicides

Some herbicides must be incorporated into the soil to be effective. Herbicides are incorporated because they are volatile and evaporate into the air if left on the soil surface or they will decompose when exposed to sunlight. Herbicides differ in their incorporation requirements; check the product label for the manufacturer's requirements.

Herbicide Sprayer Systems

  • Select a sprayer and pump that can deliver a volume of 20-50 gallons per acre. Most herbicides are applied at rates of 20-40 gallons of water per acre. Pressures of 20-40 p.s.i. at the nozzle are recommended for most herbicides. Higher pressures result in finer droplets and increase the chance for more drift. Lower pressures sometimes cause uneven spray patterns.
  • Use 50-mesh screened filters for nozzles and suction lines.
  • Select 80º-73º flat fan nozzles. Because of wear, brass tips used exclusively for applying wettable powders should not be used on more than 30 acres before being replaced. Use stainless steel or hardened stainless steel tips for longer wear. Stainless steel nozzle tips are more than twice the cost of brass tips but last about 20 times longer. Hardened stainless steel tips are only slightly more expensive than stainless steel tips but last three times longer. Ceramic nozzles are the most durable.
  • Calibrate sprayers frequently and check for wear, especially when wettable powders have been used.

Resistance Management

Pesticide resistance is an inheritable (genetic) characteristic of a pest that makes it less sensitive to a pesticide.  Repeated use of the same pesticide (or pesticides with the same mode of action) over time kills pests that are susceptible to the pesticide and leaves behind individuals that are less sensitive. These then reproduce and pass on the genes that let them survive pesticide exposure to their offspring. With herbicides, this usually takes several years to accomplish. This is because of the seed bank in the soil that preserves individuals that are not resistant for many years.

International groups have been founded for a cooperative approach to resistance management. They have assigned group numbers to pesticides to help growers make decisions on how to rotate pesticides. They are based on mode of action –how and where the chemicals in the pesticide work on the target. The Herbicide Resistance Action Committee (HRAC) and The Weed Science Society of America (WSSA) have developed a harmonized classification systems of herbicides using numbers to designate the categories. A key step in resistance management is to minimize the continuous use of herbicides with the same mode of action through rotations and combinations of products. One of the purposes of these classification systems is to make it easier for farmers and farm advisors to understand which herbicides share the same mode of action without having to actually know the biochemical basis.

Most labels now come with a group number assigned to them. Some active ingredients are available under several different product names, and sometimes different active ingredients have the same mode of action.

Resistance management may include alternating or sequencing products with different modes of action or limiting the total number of applications per season. When selecting herbicides for resistance management, use the group number as your guide and NOT the product name or active ingredient.

The most effective way to extend the useful life of an effective product is to rotate herbicides within fields if the same crop is grown or to rotate crops so that different herbicides might be used in following years. The most common weed resistance issue that we have in New England is common lambsquarters that is resistant to atrazine. To help select pesticides with a different mode of action, see chemical resistance groupings in Table 27.

Once a weed develops resistance to a group of pesticides with a particular mode of action, a higher rate of the same or a similar chemical from the same group usually will not control the weed.

There are many other techniques that can help delay the onset of resistance. Using other options and recognizing weeds that may be resistant is critical.

  • Integrate chemical control with effective cultural, mechanical, and physical options.
  • Scout fields so that you are aware of what is not controlled and can take steps to control the escaped weeds.
  • Good rate selection, spray coverage, and herbicide activation helps do the job right the first time and avoids unnecessary repeat applications: use the proper size nozzles and the correct angle or orientation and the right amount of water per acre.
  • Time postemergence applications so that the weeds are at the right stage of growth.

NOTE: The group number is specific for each type of pesticide (insecticides, herbicides, and fungicides). For example, there is no problem when using material from the herbicide Group 1 and an insecticide or fungicide from Group 1.

Groundwater Concerns

The following herbicides have the potential to impact groundwater due to their chemical characteristics and toxicological profile and have been discussed in the crops sections. Check with your state for restrictions of their use in sensitive areas.  For example, Massachusetts has Zone II designations and regulations pertaining to the use of these herbicides in those areas.

  • Atrazine (Aatrex)
  • Bentazon (Basagran)
  • Chlorthal-Dimethyl (Dacthal, DCPA)
  • Dimethanamid (Outlook)
  • Diuron (Karmex)
  • Fluthiacet-methyl (Cadet)
  • Metolachlor (Dual Magnum)
  • Metribuzin
  • Pronamide (Kerb)
  • Simazine (Princep)

Herbicides Alphabetically Listed by Active Ingredient

* Federally restricted

bensulide (Prefar): preplant incorporated herbicide for control of various grass and certain broadleaf weeds in many vegetable crops.

bentazon (Basagran): postemergence herbicide in beans, peas and sweet corn for control of yellow nutsedge, smartweed and jimsonweed.

bromoxynil (Broclean, Maestro, and others): Note: some brands are registered in some states, and not others. For examples, Maestro is not registered in NH and VT while Broclean is registered in all New England states.  Check state pesticide registrations before selecting a product to make sure it is legal to apply in your state.  Used for postemergence control of broadleaf weeds when applied at the seedling stage. For use in garlic and onions.

carfentrazone (Aim): postemergence control of many broadleaf weeds in sweet corn, pumpkin, and winter squash.

clethodim (Select Max, Intensity, IntensityOne): postemergence grass herbicide for use in many vegetable crops.

clomazone (Command): preemergence control of most grasses and some broadleaf weeds in pumpkins and peppers.

clopyralid (Stinger): postemergence herbicide for control of many annual and perennial broadleaf weeds in beets, sweet corn, spinach and turnip.

cycloate (Ro-Neet): preplant incorporated herbicide to control annual grasses, nutsedge, certain perennial grasses and many broadleaf weeds in beets and spinach. MA, NH and ME only.

DCPA (Dacthal): preemergence herbicide for control of annual grasses and certain annual broadleaf weeds in many vegetables. Restricted use in MA.

dicamba (Banvel, Clarity): postemergence herbicide in asparagus.

EPTC (Eptam): for control of annual grassy weeds, nutgrass, perennial weeds such as Johnsongrass seedlings, quackgrass and several broadleaf weeds in beans (green) and potatoes. Restricted use in VT.

ethalfluralin (Curbit, Sonalan HFP): preemergence control of many annual grasses and broadleaf weeds in some vine crops (Cucurbit) and dry beans (Sonalan).

fluazifop (Fusilade DX): postemergence grass control herbicide for use on carrots, dry bulb onions, spinach and non-bearing asparagus.

flumioxazin (Chateau or Valor):  preemergence and limited postemergence control of many broadleaf weeds and some grasses.

fomesafen (Reflex): pre- and postemergence weed control in beans and potatoes.  Can only be used every-other year!

glyphosate (Roundup): many formulations available with varying % a.i. such as Roundup PowerMax, Roundup Pro, etc., in addition to many generic glyphosate products. A postemergence herbicide absorbed by the foliage of emerged annual and perennial weeds.

halosulfuron (Sandea): preemergence and postemergence herbicide for use in asparagus, beans, corn, cucurbits, and fruiting vegetables.

imazamox (Raptor): for early postemergence weed control in dry beans, lima beans, snap beans, and english peas.

linuron (Lorox): preemergence or postemergence herbicide for control of germinating and newly established broadleaf weeds and grasses in carrots and parsley. Restricted use in VT.

mesotrione (Callisto): pre- and postemergence control of many broadleaf weeds in sweet corn and asparagus. Generics are also now available.

metolachlor (Dual Magnum): preplant incorporated and preemergence weed control in corn, potato, pumpkin, and tomato.  Restricted use in MA and VT.

metribuzin (Metribuzin): preemergence and early postemergence herbicide for control of a large number of grass and broadleaf weeds in potatoes and tomatoes. Restricted use in MA and VT.

napropamide (Devrinol): preplant incorporated herbicide for use in peppers, eggplant, tomatoes, asparagus and cole crops. For good control of barnyard grass, crabgrass, fall panicum, goosegrass, lambsquarter, pigweed and purslane. Photodegradable, must be incorporated within 24 hours by discing or watering in.

norflurazon (Solicam): preemergence used in asparagus.

oxyfluorfen (Goal): for control of certain annual grassy and broadleaf weeds in onions and crucifers.

*paraquat (Gramoxone): restricted-use pesticide. A contact "burndown" herbicide with no soil activity. May be fatal if swallowed or inhaled. Applicators must complete an EPA-approved paraquat training listed on the following website https://www.epa.gov/pesticide-worker-safety/paraquat-dichloride-training.... The training must be completed a minimum of every three years.

pelargonic acid (Scythe): postemergence contact herbicide for stale bed and directed/shielded applications in many vegetable crops.

pendimethalin (Prowl): preemergence herbicide for control of broadleaf weeds and grasses in asparagus, corn, peppers, potatoes, garlic, and onions. Restricted use in VT.

prometryn (Caparol): pre- and postemergence control of annual broadleaf weeds in carrots, celery, and parsley.

*pronamide (Kerb): preergence herbicide for weed control in lettuce.

quizalofop (Assure II): postemergence grass herbicide for use in beans and peas.

rimsulfuron (Matrix): preemergence and early postemergence herbicide for control of many grass and broadleaf weeds in potato. Restricted use in MA and VT.

sethoxydim (Poast): postemergence grass control herbicide for use in most vegetable crops. See label.

terbacil (Sinbar): preemergence and early postemergence herbicide for control of many broadleaf weeds in asparagus.

trifluralin (Treflan): preemergence herbicide that must be incorporated for control of many annual grasses and certain broadleaf weeds in many vegetable crops.

2,4-D (Amine 4): postemergence control of broadleaf weeds in asparagus and sweet corn. Restricted use in MA and VT.

Herbicides specific to corn

(not registered on other crops discussed in the New England Vegetable Managment Guide)

*acetochlor (Harness, Surpas): used for pre- and postemergence control of annual grasses and some broadleaf weeds in corn. Not registered for use in NH.

ametryn (Evik):  used for postemergence weed control in field corn and popcorn. Not for use in ME, NH, or VT.

*atrazine (AAtrex): provides season-long control of most broad-leaved weeds in sweet corn. Applied either preemergence, postemergence or in combination with other herbicides.

dimethenamid (Outlook): preemergence herbicide which provides grass and some broadleaf weed control in sweet corn.

fluthiacet-methyl (Cadet): Restricted use in some states. Not for use in fresh sweet corn. For use in field Corn, sweet corn grown for processing only, and popcorn.

nicosulfuron (Accent Q):  postemergence grass herbicide in corn.

pyroxasulfone (Zidua): used pre- or early postemergence for weed control in corn. Not registered in VT.

safluenacil (Sharpen) - used as a preplant surface, preplant incorporated, or preemergence to corn for broadleaf weed control. Not for use on sweet corn grown for fresh market use.  Some corn varieties are sensitive to injury form this herbicide. Also used as a harvest aid for dry beans.

simazine (Princep): Restricted use in some states. Used preemergence before weeds and corn have emerged.

topramezone (Impact):  postemergence control of many broadleaf weeds and some grasses in corn.

tembotrione (Laudis): postemergence herbicide for control of many broadleaf weeds in corn.

Note: Always check current registrations to be sure the herbicide is registered for the specific crop in question and state of use. Always read and follow all label instructions before using any pesticide!

Herbicides and Plastics

With the increased use of plastic culture for the production of various vegetable crops, it is very important to keep in mind a few points for proper weed management. Here are some tips:

  • If methyl bromide or Vapam fumigation is used under the plastic strips, there is no need for a herbicide under the plastic. If soil fumigation is not used and black plastic is, it may not be necessary to put a herbicide under the plastic (unless nutsedge or other weeds are excessive). If you use clear or white plastic, without soil fumigation, then you need a herbicide under the plastic mulch. To get the best results, take the following steps for herbicide application:
  • Prepare a pressed bed.
  • Apply the herbicide to the bed surface.
  • Activate the herbicide with rainfall or overhead irrigation (at least 1/2"); if the herbicide needs to be mechanically incorporated, do so and repress the bed.
  • Apply the plastic mulch. Note: Some herbicides may volatilize and cause crop injury when used under plastic mulches or row covers.  Some herbicides are prohibited from use under plastic. Be sure to observe any cautions on the product label. Wherever possible, try it on a small scale first.
  • If weeds are present between the plastic strips before planting, use a banded application of Gramoxone plus surfactant, or Roundup (if registered for stale bed use) to kill all existing vegetation. Depending on the level of weed vigor, a second application of Gramoxone plus surfactant may be needed before planting. Do not broadcast apply these herbicides to the surface of the mulch.
  • For weed control between the plastic strips, after planting, use a registered preemergence herbicide for that crop. Do not use nonregistered herbicides between strips as the crop roots will grow in that zone and, in many cases, the crop will be damaged or killed. Do not spray the surface of the plastic with any preemergence herbicides! During a rainfall the excess herbicide will wash into the holes where the crop was planted and will greatly concentrate the herbicide. Thus, the crop will be damaged or killed. When banded applications of herbicides are used, remember to adjust the rate of the herbicide downward to conform to the actual ground area being sprayed (with 30" beds and 30" areas between strips, only half the normal amount of herbicide would be required per acre since only half the amount of soil area per acre is actually being sprayed).
  • Backpack sprayers or modified boom sprayers are often used for herbicide applications in plastic culture systems. Be sure to calibrate them properly and maintain a constant pressure using a pressure gauge, especially on hand-pumped models. Maintaining a constant speed or walking pace is also necessary. Three miles per hour is a good speed (23 seconds per 100').
  • Use caution when spraying Gramoxone with a backpack or hand-held sprayer. Wear rubber boots, gloves and a mask or respirator. Avoid skin contact with the spray. If contact occurs, immediately rinse the area with water or rub soil on your skin. Soil will help soak up and bind the chemical, preventing its absorption into the skin. Spray when the wind is calm to avoid spray drift. Also, always use a surfactant and plenty of water with Gramoxone for good control.
  • Vapam is not recommended for use in the spring if the plastic is to remain in place. Under the cool soil conditions at this time of year, the soil will not aerate properly and the crop will be damaged. In plastic culture, these materials are best used if the plastic is applied during the fall before planting. Be sure with all fumigants to space the injection shanks correctly. The label recommends a 6" spacing with Vapam.
  • Herbicide use under row covers can be dangerous. Although several herbicides can be safely used under row covers, some can cause crop injury and even crop death. Generally, ventilated covers are safer than solid covers or hot caps, from an herbicide injury standpoint. This is especially true with an herbicide that is moderately or highly volatile. Test on a small scale before you apply it on a large scale.

Stale Seedbed Technique

Certain weeds may be present in crop areas which herbicides and other management techniques cannot control well in the crop system. The stale seedbed technique can result in improved weed management in problematic areas or with problematic weed species. After soils are prepared for planting, most of the weed seeds in the upper 1-2" of the soil will germinate within two weeks if soil moisture and temperature are adequate. The stale seedbed approach involves preparing the soil as if for planting, without actually planting the crop. Instead, weeds are allowed, even encouraged (with irrigation or row covers), to grow. Weeds are then killed with Gramoxone, Roundup, Scythe or flaming.

Killing emerged weeds with herbicides or flaming does not disturb the soil, and no new weed seeds will be brought close to the soil surface. After using the stale seedbed technique, care should be taken not to disturb the soil any more than is absolutely necessary during the seeding or transplanting process to minimize the amount of weed seeds that are brought up to the surface to germinate. Preemergence herbicides can also be used after to increase the efficacy of stale seedbeds. Any cultivation performed after should be kept extremely shallow (3/4"-1" maximum) so as not to reposition any additional weed seeds.

On sandy, loamy or high organic matter soils, the soil should not crust and modern seeders should still work satisfactorily. On heavy clay soils, crusting could make this technique unusable.

Stale Seedbed Steps:

  • Prepare the soil as if you are about to seed or transplant. If a soil-incorporated herbicide is used, it must be applied and incorporated at this time. The soil should have good moisture (irrigate with 1/4" of water if necessary).
  • Wait as long as possible to allow weeds to germinate and emerge. Allow weed seedlings to grow to the third leaf stage, or at least to the first true leaf.
  • If you're using transplants: flame the soil or make an application of Gramoxone, Scythe, Aim or Roundup (if registered for the crop) to the soil surface before transplanting. Transplant the crop (without dragging any additional soil off the bed) and then apply any preemergence herbicide, which you would normally use, to the soil surface.
  • If the crop will be seeded: Gramoxone, Scythe, Aim or Roundup (if registered for the crop) or flaming may be applied just before or just after seeding (see the label). After seeding, apply any preemergence herbicide which you would normally use to the soil surface.  CAUTION: If the crop has already been seeded, be careful that the flaming process does not injure the crop seed or the emerging crop seedling.

Check the current herbicide label and recommendations by crop to determine if Gramoxone, Scythe, Aim or Roundup is registered for use in that crop. Gramoxone, Scythe, Aim and flaming will have minimal long-term effect on established perennial weeds. For cucumbers, melons, squash, pumpkin, peppers and eggplant, Roundup must be applied at least three days prior to seeding or transplanting.

In cases where Roundup is registered, it can also be used for control of perennial weeds, such as quackgrass and dock, prior to soil preparation. After application, delay tillage for 3-5 days. There is no residual weed control. See the label for directions.

Table 27: Herbicides and Crops Registered

This is not a comprehensive list of all registered herbicides, but a reference of those more commonly used and registered in multiple crops.  Please refer to individual crop sections for more information on herbicides.

Herbicide
Active Ingredient
Resistance Group1
Oral LD50
Signal Word
Asparagus
Beans**
Brassicas**
Beets
Carrots
Celery
Cucurbits**
Corn, Sweet
Eggplant
Garlic
Lettuce
Onions**
Peas, green
Potatoes, Irish
Peppers
Pumpkins/Squash
Spinach
Tomatoes
Aim carfentrazone 14 5,000+ Caution R R R R R R R R R R R R R R R  R R R
Assure II quizalofop 1 5,900 Danger   R                     R          
Basagran bentazon 5 2,000 Caution   R           R         R          
Callisto mesotrione 27 5,000+ Caution  R             R                    
Caparol prometryn 5 5,000+ Caution         R R                        
Chateau/Valor flumioxazin 14 5,000+ Caution R                 R                
Command 3ME clomazone 13 5,000+ Caution R R R       R           R   R R    
Curbit/Sonalan ethalfluralin 3 3267 Danger   R         R             R   R    
Dacthal DCPA 4 10,000+ Caution     R       R   R     R           R
Devrinol napropamide 0 2,000+ Caution R   R           R           R     R
Dual Magnum s-metolachlor 15 3,425 Caution R^ R R^ R^ R^   R^ R   R^   R^ R R R^  R R^  R
Eptam EPTC 15 1,325 Warning   R                       R        
Fusilade fluazifop 1 5,000+ Caution R R     R         R R R            
Goal oxyfluorfen 14 5,000+ Warning                   R   R            
Gramoxone SL* paraquat 22 1098 Danger R R R   R   R R R R R R R R R R   R
Kerb* pronamide 3 5,000+ Caution                     R              
Lorox linuron 5 3,489 Caution R       R R   R         R R        
Matrix rimsulfuron 2 5,000+ Caution                           R       R
Metribuzin metribuzin 5 2,375 Caution R       R                 R       R
Outlook dimethenamid 15 695 Warning   R           R   R   R   R        
Poast sethoxydim 1 4,100 Warning R R R R R R R   R R R R R R R R R R
Prefar bensulide 0 960 Caution     R     R R   R R R R     R R    
Prowl pendimethalin 3 3,956 Caution R R     R   R R   R   R R R  R      
Ro-neet cycloate 15 3,129 Caution       R                         R  
Roundup glyphosate 9 5,000+ Caution R R R R R R R R R R R R R R R R R R
Sandea halosulfuron 2 1,287 Caution R R         R  R R           R R   R
Scythe pelargonic acid 17 5,000+ Warning R R R R R R R R R R R R R R R R R R
Select Max clethodim 1 5,000+ Caution R R R R R R R   R R R R R R R R R R
Sinbar terbacil 3 3,700 Caution R                                  
Stinger, Clean Slate clopyralid 4 5,000+ Caution R   R R                         R  
Treflan HFP trifluralin 3 5,000+ Caution R R R   R       R       R R R     R
2,4-D 2,4-D 4 1,161 Danger R             R                    

*Federally restricted      **not all herbicides for use in all vegetables in this group,  see crop section for details 
1Weed Science Society of America resistance code.  ^ indemnified label available in some states 

R = registered for crop; check label to confirm crop is listed before use. Note that some products are not registered in all states.

Table 28: Relative Effectiveness of Herbicides on Weed Species

Herbicide
Active Ingredient
Barnyard Grass
Crabgrass
Chickweed
Carpetweed
Fall Panicum
Fox Tail
Galinsoga
Johnsongrass (Rhizome)
Johnsongrass (Seedling)
Jimsonweed
Lambsquarter
Morning Glory
Mustard
Nightshade
Nutsedge yellow
Purslane
Pigweed
Quackgrass
Ragweed
Smartweed
Velvetleaf

Accent Q

nicosulfuron

 E

P  

   

E

 E

 

 P

 E

               

 P

     
Aim carfentrazone P P P G P P G P P G E E P G P G E P F G E
Assure II quizalofop E E N N E E N E E N N N N N N N N G N N N
Atrazine* atrazine G G E E P G E P P G E G E G P E E F E E P
Basagran bentazon P P G G P P G P P E F F G P G G P N G E G
Callisto - pre mesotrione F F E E P P E P P E G F P E P P E P E E E
Callisto - post mesotrione F F E E P P E P P E G F E E F P E P F E E
Command clomazone G G   N G G F N F F G P N   N G P N F F E
Curbit ethalfluralin E E G E E E P P E P F P   G P E E   F F F
Dacthal DCPA F E G G F E P P G P E P N P P G E P P P P
Devrinol napropamide G E E G G E G P P P F P P P P G G P G F P
Dual metolachlor G E G G E E E P F P F P P G G E G P F F P
Eptam EPTC G E F G G E F P G P G P P P G G G F P P E
Fusilade fluazifop E E N N E E N N E N N N N N N N N G N N N
Goal oxyflouren F F E E F F G P F F E P   E P E E   E E F
Gramoxone paraquat E E G E E E G P F G E G G G P G E F E G G
Impact topramezone F F E E F P E P P E G F P E P P E P E E E
Karmex diuron G G G G F G G P P G E F G G P E E P G F F
Kerb* pronamide G G   G G G P P G P G         G G   P   P
Laudis tembotrione F

P

P

F

Lorox Iinurin E E G E E E G P G E G G E G G G G P G G G
Matrix rimsulfuron E P     G E G     F F F G F P G E G P P P
Metribuzin-pre metribuzin G G G E E E E P F E E F E P P E E N G G G
Metribuzin-post metribuzin G G G E E E E P F E E F E P E E E P G G G
Outlook dimetheramid E E     E E E       P   P G G F F P P F P
Poast sethoxydim E E N N E E N E E N N N N N N N N G N N N
Prefar bensulide E E P P E E P P P N P P N P P P P N P P P
Princep simazine E G E E G G E P P E E G E G P E E F E E G
Prowl pendimethalin G E G G G E P P G P G P   P P G G   P P E
Ro-neet cycloate E E     E E P       E   N E G E E N N   F
Roundup glyphosate E E E E E E E E E E E E E E G E E G E E E

Sandea

halosulfuron

 P

   

 P

 

P

P

 

 

G

 

E

Scythe pelargonic acid E E G E E E G P F G E G G G P G E F E G G
Select clethodim E E N N E E N E E N N N N N N N N G N N N
Stinger clopyralid N N   N N N G N N P P N       N N N G P P
Treflan trifluralin G E E G G E P F G P G P P P P G G P F P P
2,4-D 2,4-D N N G G N N G N N E E G G E F G E N E F G
Zidua pyroxasulfone G E G G E E E P F P G P P G F E E P G F P

*Federally restricted herbicide

At recommended rates for your soil type or weed species: E=90% control or better, G=70%-90% control, F=50%-70% control, P=5%-50% control, N=less than 5% control

Vertebrate Pest Management

USDA Wildlife Services staff are available to assist with a variety of wildlife damage issues, including voles. Their telephone number for New Hampshire & Vermont growers is (603) 223-6832. For growers in Connecticut, Massachusetts and Rhode Island: (413) 253-2403. For Maine: (207) 629-5181.  The website is http://www.aphis.usda.gov/wildlife_damage. Trapping is often highly regulated; laws are restrictive and may be complex. Environmental Police Officers enforce trapping laws. Know the current laws and regulations before trapping any wildlife. Reductions in animal numbers by lethal methods fail to provide a long-term solution from wildlife damage in the absence of habitat modifications and exclusion methods. Most nuisance wildlife will repopulate areas soon after control efforts have ceased. Habitat modification and exclusion methods often require more expense and initial effort, but these methods will result in more durable damage prevention.

Deer                                                        

White-tailed deer are common in New England, and sweet potato leaves and vines are among their most preferred foods. In some areas, they heavily attack pumpkins, both the plants and fruit. We also see damage to butternut squash, lettuce, and occasionally tomato and other vegetable plants. They are very active at night, but during the summer they are almost as active during the day.

Fencing: Permanent mesh fencing can keep them out if it is 8-10 feet high. Such fencing restricts vehicle movement, so carefully consider turning distances, entrance locations and gate width before making an investment in permanent fencing.  Temporary electric fencing is relatively inexpensive and simple to set up. It can work very well if you bait it immediately after erecting it. Even a single electric strand at 36-40 inches can work if the deer have other feeding options. White electric tape is especially visible and works well in this application. The most common method to bait an electric fence for deer is to apply peanut butter to strips of aluminum foil and fold them (sticky side in) over the fence at about at 40-inch height, at intervals of about 30-50 feet. By licking the tasty treat they can smell, deer quickly learn that the fence can hurt them, and they keep away. Usually, the baits do not need replenishing if they are used for less than one growing season.

Repellents for deer are designed to work by odor or taste. Most commercial products are not labeled for use on vegetable crops.

Shooting is one option that growers may consider, but the rules vary greatly from state to state.  Sometimes officials will readily give out permits to shoot offending deer. Shooting is not as effective as fencing and brings on issues of safety, neighbors, and farmer image. Deer are protected species in all New England states, so check with state Fish and Game authorities or USDA Wildlife Services staff before shooting. Shooting also has safety issues.

Birds

Most birds in New England that are pests of vegetables are species with either partial or complete legal protection. State, federal and international laws/treaties are involved in their protection. This limits some of our management options. Crows and ravens often pull out seedling corn plants, to reach and consume the seed. They, along with blackbirds and starlings, frequently attack milk stage corn, especially in varieties where the ears are not well covered by the husks. Turkeys feed on kale, collards, lettuce, and mesclun mix. They also peck both green and ripe tomato fruit. Canada geese like to eat grasses and winter rye, sometimes corn. Occasionally birds cause losses by defecating on the crops. This is most common when open containers of product are placed in an open shed or barn, where English sparrows can perch in the rafters above. In that situation, growers can install netting to exclude birds from the rafter area. Canada geese defecating while grazing on grassy weeds can be an issue on low crops that are eaten fresh, like lettuce and spinach.

There are a variety of devices designed to manage bird problems.  Netting is one possibility but is most appropriate for high-value perennial crops, not most vegetables. Some of the insect and hail netting designed to protect mesclun mix and other low crops can be supported by wire hoops and stops turkey feeding. 

Taste repellents: Some taste repellents are available (methyl anthranilate for example) on some crops, but they are applicable to few vegetable crops and have variable results in our area. An exception is 9,10-anthraquinone, sold as Avipel.  It is registered (effective) as a seed treatment on corn to keep birds from walking down the rows and pulling out the seedlings. Currently, it is registered in Maine, Vermont, New Hampshire and Massachusetts.

In states where anthraquinone is not registered, growers have used two methods to reduce seedling pulling by crows and ravens.  One method is to set up tomato stakes in a zig-zag pattern, on a recently planted sweet corn field. Attach fishing line to the stakes. This seems to deter crows from landing.  When the seedlings are large enough that the birds can’t pull them out, you can reel up the fishing line, retrieve the stakes and put them in your next planting.  Another alternative is to plant sweet corn into a (low) standing stubble.  It can make the young plants harder for the crows to spot.

Scare devices can be relatively effective, especially on flocking species. All birds become habituated to scary noises, especially if they are used alone and constantly. Therefore, incorporating variability and change (sound, location, etc) is important to being successful with scare devices. Bird Damage Prevention For Northern New England Fruit Growers covers most scare devices.  Two relatively new ones not covered in that publication are Air Crow and laser lights. Air crow is a colored nylon tube/scarecrow attached to a blower. When in use, it moves constantly and can be quickly turned off when not in use. Set it in a location that makes it visible. For tall crops, that might be on a bin or stand. As with other scare devices, it is most effective when combined with other methods.  A Canadian company called Carpe diem has been selling a system of laser lights mounted on a firm mast. Some New England vegetable growers have been very happy with the results scaring various birds, despite the high cost ($2500 or more).

Auditory bird scare devices can be fairly effective, especially if the noises they create are varied.  Automated propane cannons can be effective for a relatively short time, but are very annoying to neighbors, customers, and farm workers. In New England, automatic cannons have been the source of several serious disputes with neighbors. Screamers and bangers are auditory devices that are fired from a launcher (looks like a plastic handgun).  They can cost $2.50 or more per shot but can be helpful occasionally to move out a flock of birds. Regulations cover the purchase and use of these devices. Be sure to check local regulations about their use before you begin.

Silhouettes of coyotes or other predators don’t work very well to scare birds (or other vertebrate pests of vegetables). Effigies are slightly more effective, especially those that employ movement. They are still more effective if you regularly move them to different spots. If you combine them with auditory scare devices, the effectiveness usually goes up.

Some growers employ scare-eye balloons to protect sweet corn from pecking.  Growers report that the light colored balloons work better than the dark ones. There are some larger ones with “holographic” eyes that seem to follow you as you walk by.  Growers have had relatively good results with them. With all of the balloons, it is important to suspend them from high poles 2-5 feet above the crop.   

Shooting is rarely successful at controlling bird problems. The main effect is scaring away the survivors. There are local, state and international laws that affect if, where and how shooting may be employed.

Rodents

Rodents are distinguishable by their teeth. They have sharp, opposing incisors plus strong molars to grind up material.  Between the incisors and molars, there is a broad gap with no teeth.

Woodchucks

Woodchucks especially like to eat beans, peas, carrot greens, alfalfa, clover, and grasses.  They also eat cabbage, broccoli, tomato, dandelion, and other plants. There are few succulent plants that they won’t eat.  They don't seem to prefer corn.  They are most active early in the morning and late in the afternoon. They dig extensive burrows that are used as escape cover, shelter, or overwintering sites by many other animals.  Cottontail rabbits, skunks, raccoons, foxes, coyotes, snakes, weasels, and chipmunks are among the animals that use woodchuck burrows.  Woodchucks are also prey for foxes and coyotes, bobcats, fishers, eagles, and large hawks. Please consider these points before jumping to lethal control measures for woodchucks. Both lethal and non-lethal control options are available.

Non-lethal measures: Frightening devices don’t seem to be effective to deter woodchuck feeding.  Although some taste repellents are available, they are not very practical for vegetable crops that people will be eating. Fencing can be very effective but restricts vehicle movement. Also, if you depend on fencing, be sure the woodchuck burrow is not inside the fence. Since woodchucks can climb and burrow, the most effective alternative is electric fencing. An effective combination is one wire 4 inches off the ground and a second at 8 or 9 inches high.  Dealers offer a wide variety of plug-in and battery powered, UL-approved chargers.  Keep the fence clear of any obstructions or vegetation that might short out the electric pulses.

If you use non-electric fencing, buy a mesh size smaller than 2 X 2 inches, especially close to the ground.  (The young ones can sometimes squeeze through that mesh size.)  Common chicken wire rusts away quickly -- the woodchucks may push through it by the second growing season.  Non-electric fencing should have some means of preventing the woodchucks from burrowing underneath.  You could bury the fence to a depth of 10-12 inches.  Or you could bend the lower 1 foot 90 degrees outward, to form an "L", then lay it on the ground and securely pin the L into the ground.  Another option is laying an 18-inch wide strip of galvanized fencing on the ground below the fence, and keep the vertical fence flush with it.  Non-electric fences need to be at least 3 feet high.  Bending the top 12-15 inches outward at about a 45-degree angle will help deter them from climbing a non-electrified fence. Don't neglect the gate.  That is often the spot where defenses are the weakest. If animals try to burrow underneath, install a board dug into the ground and flush with the bottom of the gate, or lay down a length of fencing as described above.

Live trapping is a possibility in some situations, but it carries risks. Small details in setup make big differences in the success rate. If a carrier of rabies were trapped, handling it could be a risk to any non-vaccinated person who was exposed. Trapping and translocating a woodchuck from its home is subjecting the “humanely trapped” animal to a prolonged, very stressful ordeal that often ends in its death. Suitable habitat is farmland with open fields and an abundance of short grasses.  Farmers or gardeners are not likely to agree to your releasing animals on their property, and woodchucks are not woodland creatures. In some New England states, laws prohibit the practice of transporting and releasing trapped animals.

The most effective technique is to place the trap directly at the burrow entrance and use a barrier of boards or other material to direct the animal into the trap as it leaves its burrow. No bait is needed in this situation. Trap placement elsewhere is much less effective, but sometimes the woodchuck can be enticed inside with fresh apple slices or fresh carrots or lettuce.  Change baits daily.    

Lethal controls: use them cautiously, after careful thought. They can end up killing non-target animals. Gas cartridges are cardboard cylinders filled with slow-burning, asphyxiating chemicals. Locate an active burrow, and treat when you are sure the woodchuck is inside. Find and close all but one entrance, and prepare a sod plug for the opening. Attach the cartridge to a 3-foot branch, light the fuse, and place it well inside. Immediately seal the entrance. Most failures with cartridges are from the fuses going out (often because loose dirt covered then, or they were thrown). Sometimes they fail because the woodchuck was somewhere else when the burrow was fumigated. Upon its return, it just re-opens the burrow. Never use a gas cartridge near flammables or under a wooden structure.

Conibear traps are body-gripping steel traps that almost instantly kill an animal that tries to move through.  If a pet or other non-target animal walks through one, there is no second chance. Use these traps only where you are certain the intended target is the only animal that can enter.  They are usually placed just inside the burrow, to trap the occupant as it enters or leaves. Conibear sizes 160 and 220 are appropriate sizes for woodchucks. This risky method requires permits or licenses in many areas, so check first before using this.

Shooting is an option that has a low risk of harming non-target animals if done carefully. In many New England states, woodchucks can be shot by anyone with a hunting license, or by farmers on their own property, protecting their crops.  In most New England states, there is no closed season on woodchucks. A .22 caliber rifle with hollow point cartridge is the most commonly employed weapon for woodchuck control. When shooting, take extreme care that the area is safe for a shot. A .22 caliber long rifle bullet can travel nearly a mile if it does not strike something first.  They easily ricochet off hard surfaces.

Voles

Voles can attack a wide range of plants. In New England, they have been reported attacking tomato, asparagus, potato, sweet potato, carrot and other vegetables. Grasses are especially favored food for several species of voles. We have four vole species [meadow, southern redback, rock, pine] that can cause problems in New England, but most suspicion falls on meadow voles and pine voles. Pine voles primarily live and feed in tunnels underground, and readily attack root crops: carrot, beet, potato and sweet potato. They have very short tails, never longer than their hind feet. Meadow voles largely live above-ground and have tails that are longer than their hind feet. Voles have less prominent eyes than mice, and their ears are buried in the fur. Mice have prominent ears.

We have few options to manage pine voles on vegetable farms. Problems are most common in soils that are adjacent to woodlands or orchards.  Soils that are poor for pine voles are those that are commonly waterlogged, or have very high clay content, or are almost entirely sand. Tunneling is difficult in those conditions. Meadow voles mostly live above ground and often chew off plants just above the soil line, especially if there is a lot of vegetation to hide them. Weedy fields and field edges are common sites of attack.  Sometimes voles attack when very young plants are still in liner or plug trays on the ground in a high tunnel. Meadow voles have an extremely high reproduction rate, so their populations can rebound rapidly after controls are implemented.

Voles prefer areas with good cover, so maintaining good weed control is important to reduce the risk of vole problems. Piles of debris placed right next to high-risk crops (like a high tunnel full of transplants) are invitations for vole problems. If you use a mulch, it can encourage vole problems. This includes organic materials like grass clippings, woven blankets, or extruded materials like plastic.

Rodenticides: There are rodenticides registered for use against voles in orchards, fruit groves, nurseries, and highbush blueberries.  Currently, there are no rodenticides registered for use in vegetable fields. A limited number of products might be legal for use (gray zone) in high tunnels and in and immediately around other buildings, but they may be of very limited use. There are quite a few rodent baits registered for commensal (in and around buildings) rodent control, but the term vole rarely appears on their labels. For the most part, commensal rodent control products are intended for mice and rats, and the bait is formulated to appeal to those species, not voles.

Be very cautious about using the second-generation anticoagulants (brodifacoum, difethialone, bromadiolone). These materials (esp. brodifacoum) have been found in an amazingly high percentage of dead, sick or injured predatory birds and predatory mammals in the northeast states. EPA responded to this problem by drastically reducing the availability of brodifacoum products for use by non-licensed applicators.  But it is still available for licensed applicators, in and around buildings. If pets or wildlife can reach the bait, they can be poisoned.

In most cases, the rodenticide labels state that rodent baits must be used in bait stations. In part, this is to reduce the risk of direct poisoning to domestic animals. But secondary poisoning can occur (brodifacoum for example), where one animal eats the bait and becomes weakened or dies. Then a second animal eats the target pest and becomes a victim.

Rodenticide labels are usually available to examine at the manufacturer’s website. Common manufacturers that include some field-applied products registered in New England include:

There are many additional manufacturers that provide materials for commensal (in and around homes) rodent control. If you cannot tell if a rodenticide is registered for use in your state, check the registration list. Each New England state has a list of pesticides that are registered in that state for that year. Often the list is incomplete early in the year. In most states, that list is available through the state pesticide control division.

Trapping is a possibility for meadow, redback and rock voles, but it isn’t very practical.  Tiny details have a major effect on trapping success. In a situation where high-value plants are concentrated and damage is significant (high tunnel full of plugs or transplants for example) careful trapping might help.  In that case, one or more vole tubes might be a good situation for a trap. Using scrap lumber, you create a 16-18 inch long narrow tube, whose rectangular interior dimensions fit a standard mousetrap, leaving enough room for the spring bar to clear the ceiling. For most traps, that inside measurement would be 2’’ wide and 2.5” high. At the center of one side, leave an opening large enough to easily insert a mouse trap. Consider placing two traps in a tube, each one with the trigger facing its respective end. Then gently set the tube in the desired location and place a piece of cardboard to cover the side opening. No bait is needed. Voles like traveling in protected runs and this catches them as they try to use an inviting runway. It keeps the trap safe from your cat or dog, and your workers’ toes.  One spot to place a tube is where there is an established path between the trays of plug plants.  

Vole Problems in High Tunnels/Greenhouses

Growing vegetables inside structures presents a different set of regulations, compared to outdoors. The use of rodenticides is one area that is not very clearly defined in this situation. Many rodenticides are labeled for “commensal” (means in and around buildings) rodent control, not for use on or around a crop. When you grow a crop inside the structure, that brings up new legality issues. Also, commensal rodenticides are typically formulated to entice rats and mice, not voles. Cats find warm greenhouses and high tunnels especially inviting, and this behavior increases the risk of poisoning them if you use rodenticides in or around those structures. As described above, secondary poisoning is a significant concern with some rodenticides.

For a greenhouse in which you plan to grow vegetables, it is possible to reduce the chances of having vole problems by using ¼ inch mesh hardware cloth to seal all openings at or near ground level. Bury the edges well. High tunnels are much harder to protect from vole entry. In both high tunnels and greenhouses, control weeds well inside.  Just outside, keep the vegetation well mowed or controlled with herbicides. 

Other Rodents

Gray Squirrels commonly raid ears of corn, especially if they are close to woods. Damage is sporadic, so usually, controls are not warranted.  Gray squirrels are protected species in all New England states.

Mice tend to be seed eaters, though some will feed on fruits when given an opportunity.  The white-footed mouse is a common New England species that frequently moves into buildings, especially in fall and winter. Usually, we do not see evidence of them attacking vegetable plants. Mice have prominent ears and eyes, while voles tend to have smaller ears and less prominent eyes.

Muskrats are rodents that are strongly associated with ponds, marshes or slow rivers.  They eat aquatic plants, but occasionally attack corn, beans, wheat or oats that are growing adjacent to wetlands. Attack is uncommon, so it rarely warrants control.

Rats (Norway, roof) occasionally attack picked vegetables stored in containers indoors, but rarely are reported attacking the plants in the field. Rat control can be very demanding.  It requires eliminating food sources, plugging holes in walls, and careful use of traps and/or rodenticides. Rats are notoriously reluctant to try new foods (like rodent baits), and resistance to rodenticides is a problem. Rat control in buildings isn’t the focus of this reference, so you’ll need to look elsewhere for details.

Lagomorphs (Rabbits and Hares)

Rabbits and hares are close relatives of rodents. Cottontails are the most common species attacking vegetables. We have two species here: New England cottontail and the larger Eastern cottontail. They eat a wide variety of vegetable plants [carrot, pea, bean, beets, lettuce, spinach and others].  They do not tend to feed on corn, squash, tomato, cucumber, potato. They eat many flowers (tulips for example). Good cover is especially important to help hide these animals from their many enemies. Western Connecticut has European hare, and northern New England has varying (snowshoe) hare, but these are not usually associated with damage to vegetables. 

We most commonly use fencing for lagomorph control. Two-foot high fence with 1-inch mesh is sufficient if it is buried slightly into the ground. Chicken wire can work, but very young rabbits can sometimes squeeze through.  Electric fencing designed for woodchucks or raccoons is often effective and less expensive than erecting mesh fencing.

Thiram is fungicide that is a taste repellant that works on rabbits, but it is not labeled for use on vegetables. Shooting may be an option in some situations, but these are protected species, so be sure to check first on state regulations. There are safety issues with shooting. We most commonly use a .22 rimfire rifle for rabbit control.

Rabbits strongly prefer to be in thick cover, so good weed control and mowing edges can help reduce the risk of damage.

Carnivores 

Raccoons                                              

Raccoons are a common animal that are especially active at night. Before the raccoon strain of rabies moved through New England (mid 1990’s), raccoon damage to sweet corn was a very serious problem, and many growers used electric fences to protect sweet corn in the milk stage. Today sweet corn damage from raccoons is less common. Raccoons also attack cantaloupe and watermelon fruits. They are most active at night.

Fencing: The most common and effective control for raccoons is using electric fences, with one wire at 6-inch height and a second at 12 inches.  Sometimes a single wire at 6 inches works well. Be certain that vegetation is cleared from the fence, or it will reduce the shock an animal receives when it contacts the wire.  Fencing will limit vehicular traffic, but temporary clip-on gates are easy to install.

Trapping: Some farmers employ trapping, but it can be difficult and time-consuming to do properly and may be subject to local and/or state laws. The raccoon is a protected species, and the rules vary state to state. Live trapping requires a sturdy trap and an effective bait. Sardines are one bait that has worked. Transporting trapped animals is illegal in some New England states. Conibear (lethal body-gripping) traps can work but must be placed in a spot where pets cannot get to them. They do pose a risk to other wildlife, as well as pets and people. An animal that steps into one does not get a second chance. Leghold traps can be effective, but it is tricky to set them properly, they pose a risk to pets, wildlife, and possibly people. If you do use traps and need to move a dead raccoon, be careful to use rubber gloves.  Raccoons can harbor the nematode Baylisascaris procyonis (“raccoon roundworm”) that can parasitize people. Raccoons can be infected with rabies virus, which is lethal to people.

Other Carnivores

Opossum occasionally feeds on sweet corn, and some fruits. It is an omnivore that feeds on carrion, and also eats fruits & grains. It is more active at night than by day. Electric fencing is the most appropriate control method.

Red fox is common in New England and sometimes feeds on ears of corn or cantaloupe fruits. We rarely get reports of significant damage.  Foxes are valuable predators of voles and other pests, so we generally consider their presence beneficial. They are protected in all New England states.

Black bears are more common in northern New England than southern New England. Bears readily attack sweet corn and field corn in the milk stage. Damage often occurs in large spots in the middle of the field, where the bears pull down all of the stalks and are hidden from view. Since black bears are protected by laws, contact your state Fish & Game officials or USDA Wildlife Services staff for assistance if you have a bear problem.

Resources

Bird Damage Prevention For Northern New England Fruit Growers https://extension.unh.edu/resource/bird-damage-prevention-northern-new-england-fruit-growers

Carpe diem technologies www.carpediemtechnologies.com  offers laser bird scare devices.

Dealing With Woodchuck Damage https://extension.unh.edu/resources/files/Resource000562_Rep584.pdf

Managing Voles in New Hampshire Orchards and Highbush Blueberries https://extension.unh.edu/resources/files/Resource003424_Rep4893.pdf

OESCO is located in Conway, Massachusetts and has been very helpful to many orchardists in figuring out how to set up and what to order for bird netting.  Their website is at www.oescoinc.com  and telephone number is 1-800-634-5557.  They also have a detailed catalog online.

Orchard Equipment Supply Company (OESCO), Conway, MA. www.oescoinc.com.
1-800-634-5557. 

USDA Wildlife Services staff are available to assist with a variety of wildlife damage issues, including voles. Their telephone number for New Hampshire & Vermont growers is (603) 223-6832. For growers in Connecticut, Massachusetts and Rhode Island: (413) 253-2403.  For Maine:  (207) 629-5181.  The website is http://www.aphis.usda.gov/wildlife_damage/

Wellscroft Fence Systems Chesham, NH. www.wellscroft.com
1-855-327-6336.