Bean, dry-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 (as they are nocturnal) to find them, if practical. Scratch the soil at the base of plants to find larvae in the daytime.

Management-chemical control: HOME USE

  • azadirachtin (neem oil)-Some formulations are OMRI-listed for organic use.
  • Bacillus thuringiensis var. kurstaki (Bt)-Some formulations are OMRI-listed for organic use.
  • bifenthrin
  • carbaryl-To avoid harming bees, do not apply products containing carbaryl to plants in bloom.
  • esfenvalerate
  • insecticidal soap-Some formulations are OMRI-listed for organic use.
  • plant essential oils (rosemary, etc.)-Some have demonstrated efficacy against lepidopteran larvae. Some formulations are OMRI-listed for organic use.
  • pyrethrins (often combined with other ingredients)-Some formulations are OMRI-listed for organic use.
  • spinosad-Some formulations are OMRI-listed for organic use.
  • zeta-cypermethrin

Management-chemical control: COMMERCIAL USE

  • acephate (numerous products) at 0.75 to 1 lb ai/a. PHI 14 days. REI 24 hr. Do not feed treated vines. Do not exceed 2 lb ai/a per year.
  • Bacillus thuringiensis (Javelin)-See product labels for rates. PHI 0 days. REI 4 hr. Add an appropriate spreader-sticker to enhance control. Most effective on small larvae. Some formulations are OMRI-listed for organic use.
  • beta-cyfluthrin (Baythroid XL, Tombstone Helios) at 0.0065 to 0.025 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 14 days. Do not exceed 0.05 lb ai/a per season. Do not feed treated vines or hay to livestock. Toxic to bees, fish and aquatic invertebrates. Only registered for use in WA
  • esfenvalerate (Asana XL) at 0.03 to 0.05 lb ai/a. PHI 21 days. REI 12 hr. Do not exceed 0.2 lb ai/a per year. Do not feed or graze treated vines.
  • lambda-cyhalothrin (Warrior II) at 0.015 to 0.03 lb ai/a. PHI 21 days. REI 24 hr. Do not graze or feed to livestock. Do not exceed 0.12 lb ai/a per year. Do not apply within 25 ft of an aquatic habitat, 150 ft if applied by air.
  • malathion (numerous products) at 1.5 lb ai/a. PHI 7 days. REI 12 hr.
  • methomyl (Lannate SP) at 0.45 to 0.9 lb ai/a. PHI 14 days to harvest, feeding vines, or hay. REI 48 hr. Do not exceed 4.5 lb ai/a per year.
  • novaluron (Rimon .83 EC) at 6 to 12 fl oz/a. Do not apply more than 36 fl oz/a per season. PHI 24 hr. REI 12 hr.
  • spinetoram (Radiant SC) at 0.0313 to 0.0625 lb ai/a. PHI 28 days. REI 4 hr. Retreatment interval 4 days. Do not exceed six applications or 0.094 lb ai/a per season. Follow resistance management procedures on the label.
  • zeta-cypermethrin (Mustang; Mustang Max) at 0.008 to 0.025 lb ai/a (Mustang Max) or 0.016 to 0.05 lb ai/a (Mustang). PHI 21 days. REI 12 hr. Retreatment interval 5 days. Do not exceed 0.15 lb ai/a (Mustang Max) or 0.3 lb ai/a (Mustang) per year. Do not apply within 25 ft of an aquatic habitat, 150 ft if applied by air.

Related Links