Insect Control

Nonchemical control: Flea beetles, leafminers and the cabbage maggot can be controlled in spring crops with spunbonded row covers. Cover at seeding and seal the edges with soil to exclude the cabbage maggot fly, which lays eggs at the base of the young turnip or rutabaga seedlings. Rotate fields so that flies do not emerge under row covers. Row covers are most effective for spring crops. Use a non-heating row cover, such as Proteknet, to protect fall turnips and rutabagas from cabbage maggot during August and early September, as spunbonded row covers can trap too much heat and cause reduced yield and root quality. Aphids are generally kept below damaging levels by natural enemies. If using row cover, do not place over crops with aphids present as the cover will exclude natural enemies and cause outbreaks of aphids under the cover.

NOTES:  For the insecticides listed below, one product trade name and formulation is provided for each active ingredient (AI) as an example of rates, preharvest interval (PHI), restricted entry interval (REI), and special instructions. In many cases, there are other products available with the same AI. Please see Table 26 and Insecticides Alphabetical Listing by Trade Name for more information on these insecticides.

The designation (Bee: L, M, or H) indicates a bee toxicity rating of low, moderate, or high. See the Protecting Honeybees and Native Pollinators section for more details.

The symbol * indicates a product is a restricted use pesticide. See Pesticide Safety and Use for more details.

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.

Aphid, primarily Cabbage Aphid (Brevicoryne brassicae)

See cabbage aphid in the Cabbage section. Green peach aphid is an occasional pest of rutabaga and turnip; see in the Pepper section for more information.

alpha-cypermethrin (Fastac* EC): 3.2 to 3.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.

azadirachtin (Azatin OOG): 4 to 16 oz/A foliar or drench, 4 to 16 oz/100 gal in greenhouses; PHI 0d, REI 4h, Bee:L, Group un. When using lower rates, combine with adjuvant for improved spray coverage and translaminar uptake.

bifenthrin (Brigade* 2EC): 2.1 to 6.4 oz/A; PHI 21d, REI 12h, Bee: H, Group 3A. For use on turnip greens only.

Chromobacterium subtsugae strain PRAA4-1 (GrandevoOG): 2 to 3 lb/A; PHI 0d, REI 4h, Bee: M.

dimethoate (Dimethoate 4EC): 8 oz/A; PHI 14d, REI 48h, Bee: H, Group 1B. For turnip greens and roots only.

dinotefuran (Venom): 2 to 3 oz/A foliar; PHI 1d, REI 12h, Bee: H, Group 4A. For turnip greens only.

flonicamid (Beleaf 50SG): 2 to 2.8 oz/A; PHI 3d, REI 12, Bee: L, Group 9C.

flupyradifurone (Sivanto): 7 to 10.5 oz/A for foliar application. 7 to 14 oz/A for soil application on turnip greens only; PHI 7d foliar, PHI 1d soil, REI 4h, Bee: L, Group 4D.

imidacloprid (Admire Pro): 4.4 to 10.5; PHI 21d, REI 12h, Bee: H, Group 4A. For soil applications only.

malathion (Malathion 57EC): 1 to 1.6 pt/A rutabaga, 1 to 2 oz/A turnip; PHI 7d rutabaga, PHI 1d turnip, REI 12h, Bee: H, Group 1B.

pymetrozine (Fulfill): 2.75 oz/A; PHI 7d, REI 12h, Bee: L, Group 9A. Turnip greens only.

pyrethrin (PyGanic EC5.0OG): 4.5 to 17 oz/A; 0.25 to 0.50 oz/gal, 3 gal/1000 sq ft in greenhouse for backpack sprayers; PHI 0d, REI 12h, Bee: M, Group 3A.

sulfoxaflor (Transform WG): 0.75 to 1.5 oz/A; PHI 7d, REI 24h, Bees: H, Group 4C.

thiamethoxam (Actara): 1.5 to 3 oz/A; PHI 7d, REI 12h, Bee: H, Group 4.

thiamethoxam (Platinum): 5 to 12 oz/A; REI 12h, Bee: H, Group 4. Systemic insecticide used at seeding or within 24 h of seeding as an in-furrow or narrow surface band with sufficient water for incorporation, or in drip irrigation. 

Cabbage Maggot

See Cabbage section for more information on cabbage maggot. Both spring and fall crops are susceptible to maggot damage. Cooler soils in early fall allow survival of eggs from late-season maggot fly. Use drop nozzles directed to base of plant. Use at least 100 gal water/A.

chlorpyrifos (Lorsban* 4E): Pre-plant: 4.5 pint/A ; At or post-plant: 1.6 to 2.75 oz/1000 row ft (turnip) or 1.6 to 3.2 oz/1000 row ft (rutabaga); PHI 30d, REI 24h, Bee: H, Group 1B. Apply pre-plant as a broadcast spray and incorporate same day into top 2 to 4" of soil, or apply to direct seeded crops as a 4" band over the row at planting time. May be applied to transplanted turnips as spray directed to base of plants immediately after setting. Do not add adjuvants or apply as a foliar spray.

diazinon (Diazinon* AG500): 2 to 4 qt/A; REI 4d, Bee: H, Group 1B. Broadcast and incorporate to a depth of 4 inches just before planting. For rutabaga only.

Foliar Treatment for Adult Flies:

alpha-cypermethrin (Fastac* EC): 3.2 to 3.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.