Spinach-Armyworm and cutworm

Includes

Beet armyworm (Spodoptera exigua)
Bertha armyworm (Mamestra configurata)
Western yellowstriped armyworm (Spodoptera praefica)
Black cutworm (Agotis ipsilon)
Variegated cutworm (Peridroma saucia)

Pest description, crop damage and life history

See:

Management-cultural control

Weed control is important. Lambsquarters and wild mustard attract egg-laying females and provide a source of food for larvae. Fall tillage can help destroy overwintering pupae.

Home gardeners: Control weeds, grasses, and debris in the vegetable garden that provide cover; hand-pick cutworm larvae, using a flashlight to find them, if practical. Scratch the soil at the base of plants to find larvae in the daytime.

Management-chemical control: HOME USE

Apply any one of these materials to the soil surface at first sign of cutworm activity. Consult label. Minimum preharvest interval (PHI) varies with crop. Difficult to control.

  • azadirachtin (neem oil)-Some formulations are OMRI-listed for organic use.
  • Bacillus thuringiensis var. kurstaki (Btk)-Some formulations are OMRI-listed for organic use.
  • Beauvaria bassiana-Some formulations are OMRI-listed for organic use.
  • carbaryl
  • cyfluthrin
  • imidacloprid
  • kaolin-Applied as a spray to foliage, it acts as a repellent to some insect pests. Some formulations are OMRI-listed for organic use.
  • permethrin
  • plant essential oils (rosemary, etc.)-Some have demonstrated efficacy against lepidopteran larvae. Some formulations are OMRI-listed for organic use.
  • pyrethrins-Some formulations are OMRI-listed for organic use.
  • spinosad-Some formulations are OMRI-listed for organic use.
  • zeta-cypermethrin

Management-chemical control: COMMERCIAL USE

  • alpha-cypermethrin (Fastac EC) at 0.020 to 0.025 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.075 lb ai/a per season.
  • Bacillus thuringiensis (Javelin) at 01.2 to 1.5 lb/a. PHI 0 days. REI 4 hr. Acts slowly; may need multiple applications. An adjuvant improves control. Most effective on small larvae. Some formulations are OMRI-listed for organic use.
  • beta-cyfluthrin (Baythroid XL) at 0.007 to 0.025 lb ai/a. PHI 0 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.1 lb ai/a per season.
  • beta-cyfluthrin/imidacloprid (Leverage 360) at 0.07 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.1 lb ai/a beta-cyfluthrin or 0.2 lb ai/a imidacloprid per season.
  • bifenthrin (Brigade WSB) at 0.033 to 0.1 lb ai/a. PHI 40 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.4 lb ai/a per season.
  • bifenthrin (Capture LFR) at 0.04 to 0.08 lb ai/a at plant or PPI. Do not exceed 0.1 lb ai/a per season as an at-plant treatment.
  • bifenthrin/avermectin (Athena) at 0.05 to 0.12 lb ai/a. PHI 40 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.056 lb ai/a avermectin or 0.4 lb ai/a bifenthrin per year. Limit 2 treatments.
  • bifenthrin/imidacloprid (Brigadier) at 0.08 to 0.096 lb ai/a. PHI 40 days. REI 12 hr. Do not exceed 0.24 lb ai/a imidacloprid and 0.24 lb ai/a bifenthrin per season. Retreatment interval 7 days.
  • borate complex (Prev-Am Ultra) at 0.4% solution. Apply to complete coverage. REI 12 hr. OMRI-listed for organic use.
  • Burkholderia spp. (Venerate XC) at 1 to 8 quarts/a product. PHI 0 days. REI 4 hr. OMRI-listed for organic use.
  • carbaryl (Sevin 4F) at 1 to 2 lb ai/a. PHI 14 days. REI 12 hr. Retreatment interval 7 days. Limit 5 treatments per year. Do not exceed 6 lb ai/a per season.
  • chlorantraniliprole (Coragen) at 0.045 to 0.098 lb ai/a as soil, chemigation or foliar treatment. PHI 1 day. REI 4 hr. Retreatment interval 3 days foliar, 10 days drip chemigation. Do not exceed 0.2 lb ai/a per season
  • chlorantraniliprole/thiamethoxam (Voliam Flexi) at 0.1 to 0.172 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.172 lb ai of thiamethoxam or 0.2 lb ai of chlorantraniliprole per acre per growing season.
  • Chromobacterium subtsugae (Grandevo) at 0.3 to 0.9 lb ai/a per 100 gal. PHI 0 days. REI 4 hr. OMRI-listed for organic use.
  • cyantraniliprole (Exirel) at 0.045 to 0.088 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 5 days. Do not exceed 0.4 lb ai/a per year.
  • cyfluthrin (Tombstone) at 0.013 to 0.05 lb ai/a. PHI 0 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.2 lb ai/a per season.
  • cyfluthrin/imidacloprid (Leverage 2.7) at 0.08 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.17 lb ai/a cyfluthrin or 0.24 lb ai/a imidacloprid per year.
  • diazinon (Diazinon 50W) at 2 to 4 lb ai/a. Broadcast before planting and incorporate in soil. REI 3 days.
  • emamectin benzoate (Proclaim) at 0.008 to 0.015 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.09 lb ai/a per season. Do not graze. For armyworm.
  • GS-omega/kappa-Hxtx-Hv1a (Spear Biological Insecticide) at 0.8 lb ai/a. PHI 0 days. REI 4 hr. Do not exceed 2 lb ai/a per year.
  • indoxacarb (Avaunt) at 0.065 lb ai/a. PHI 3 days. REI 12 hr. Do not exceed 0.26 lb ai/a per crop. Retreatment interval 3 days.
  • methomyl (Lannate SP) at 0.45 to 0.9 lb ai/a. PHI 7 days. REI 48 hr. Do not exceed 3.6 lb ai/a per season. Limit 8 treatments per year. Do not apply to seedlings less than 3 inches in diameter or when temperature is below 32°F.
  • methoxyfenozide (Intrepid 2F) at 0.06 to 0.12 lb ai/a early-season, or 0.12 to 0.16 ai/a mid- to late-season. PHI 1 day. REI 4 hr. Do not exceed 1 lb ai/a per season.
  • permethrin (Loveland Permethrin, Permethrin Cutworm Bait) at 0.1 to 0.2 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 3 days foliar, 10 days bait. Do not graze or feed treated crop refuse to livestock. Do not exceed 0.2 lb ai/a foliar or 1 lb ai/a bait per season.
  • spinetoram (Radiant SC) at 0.039 to 0.078 lb ai/a. PHI 1 day. REI 4 hr. Retreatment interval 4 days. Do not exceed 0.266 lb ai/a per season. Do not apply to seedling leafy vegetables grown for transplant within a greenhouse, shade house, or field plot. Limit 6 treatments per season. Armyworms.only.
  • spinosad (Success, Entrust SC) at 0.063 to 0.125 lb ai/a. PHI 1 day. REI 4 hr. Do not exceed 0.45 lb ai/a per crop. Limit 6 treatments per season. Entrust SC is OMRI-listed for organic use.
  • tebufenozide (Confirm 2F) at 0.09 to 0.12 lb ai/a early year; 0.12 lb ai/a mid to late year. PHI 7 days. REI 4 hr. Do not exceed 0.625 lb ai/a per season. Reapplication on a 10- to 14-day schedule may be necessary for heavy infestations. An adjuvant improves control. Armyworm only.
  • thiamethoxam/chlorantraniliprole (Durivo) at 0.195 to 0.257 lb ai/a applied to the soil. PHI 30 days. REI 12 hr. Do not exceed 0.172 lb ai of thiamethoxam or 0.2 lb ai of chlorantraniliprole per acre per growing season.
  • zeta-cypermethrin (Mustang) at 0.028 to 0.05 lb ai/a for cutworm, 0.04 to 0.05 lb ai/a for armyworm. PHI 1 day. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.3 lb ai/a per season.

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