Field Identification
A migratory moth caterpillar that damages corn, sorghum, turf, and many vegetables, often boring into whorls or fruit. Larvae show a distinctive inverted Y on the head capsule and four dark spots in a square on the rear segment.
Color varies from green to brown to nearly black; smooth-bodied with longitudinal stripes. Feeding leaves ragged holes and abundant frass in whorls.
How to Deal With It
Organic Control Methods
Plant early or use transplants to outpace late-season flights; destroy crop stubble; encourage bats and insectivorous birds with habitat.
Trichogramma spp. attack eggs; Bacillus thuringiensis kurstaki or aizawai on small larvae; nuclear polyhedrosis viruses build in outbreaks naturally.
Intercrop with diverse flowering plants to support parasitoids; hand-crush egg masses and young larvae on garden scale.
For corn, apply mineral oil to silks to limit ear entry where appropriate; exclude moths from small plots with netting.
Bt products applied to whorls and leaf axils; spinosad for tougher infestations where organic-approved; avoid spraying open flowers.
Let Nature Handle It
Natural Enemies
- Parasitic Wasps
- Predatory Stink Bugs
- Ground Beetles
- Birds
Threat Map