Apple-Lacanobia fruitworm

Lacanobia subjuncta

Pest description and crop damage The adult moth is about 1 inch long and has a distinctive color pattern of scales on the wing that range from light brown to black The appearance of the larva varies with age: young larvae resemble green fruitworms (green with a lateral stripe), while older larvae may be bright green to tan to a light red or brick color. Mature larvae have a herringbone pattern on its dorsal side and may be up to 2 inches long.

Larvae can defoliate shoots. Older larvae also feed on the fruit.

Biology and life history The insect overwinters as a pupa in the soil and adults emerge in May and June. Eggs may be deposited in fruit trees or on weed hosts. The first generation larvae appear in June and July and feed principally on foliage, but may also feed on fruit. Larvae are voracious feeders and can defoliate shoots in a few days. The emergence of second generation adults begins in late July and they are active through October. Larval feeding from the second generation begins in mid-August and larvae can be found in October.

Scouting and thresholds Examine fruit clusters shortly after fruit set for the small green larvae. They tend to occur in clumps, so thorough monitoring is required.

Management-cultural control

Home orchardists: Adults can be collected in black-light traps. Hand-pick larvae when thinning fruit.

Management-chemical control: HOME USE

Spring and summer

  • azadirachtin (neem oil)-Some formulations are OMRI-listed for organic use.
  • carbaryl-Highly toxic to bees.
  • pyrethrins-Some formulations are OMRI-listed for organic use.
  • spinosad-Highly toxic to bees. Some formulations are OMRI-listed for organic use.

Management-chemical control: COMMERCIAL USE

Spring and summer

  • emamectin benzoate (Proclaim 5SG) at 3.2 to 4.8 oz/a in up to 100 gal of water per application. Do not exceed 14.4 oz/a per growing season. PHI 14 days. [Group 6]
  • flubendiamide (Belt SC) at 3.0 to 5.0 oz/a in a minimum of 100 gal of water per application. Do not exceed three applications or 15 oz/a per growing season. PHI 14 days. [Group 28]
  • indoxacarb (Avaunt ) at 3 to 6 oz/a in up to 100 gal of water per application. Make no more than 3 applications prior to hand-thinning. No hand thinning after the 4th application. Make no more than 4 applications per growing season. Do not apply more than 24 oz/a per growing season. Apply in spray volume of up to 200 gal/a. PHI 14 days. [Group 22A]
  • spinetoram (Delegate WG) at 4.5 to 7 oz/a in up to 100 gal of water per application. Do not exceed four applications or 28 oz/a per growing season. PHI 7 days. [Group 5]
  • spinosad (Entrust 80WP or 2SC) at 2 to 3 oz or 6-10 fl oz /a in up to 100 gal of water per application. Do not exceed 9 oz or 29 fl oz /a per season. PHI 7 days. [Group 5] larvicidal] OMRI-listed for organic use.
  • spinosad (Success Naturalyte ) 6 to 10 oz/a in up to 100 gal of water per application. Use only on young larvae. Do not exceed 29 oz/a per growing season. PHI 7 days. [Group 5]
  • tebufenozide (Confirm 2F) at 10 to 20 oz/a in up to 100 gal of water per application. Do not apply more than 120 oz/a per growing season. PHI 14 days. [Group 18A]