Fall Armyworm

Spodoptera frugiperda

Full grown larva.

Typical damage to corn.

Fall armyworm are migratory and do not overwinter in Kansas to any significant extent. Larvae are highly variable in coloration, but the thickest stripe on the side is always dark, and the head capsule bears a distinctive inverted 'Y'. Damage occurs in midsummer, when larvae cut large holes in whorl-stage leaves. Later, large holes may be cut in the stalks at the nodes. Control at the whorl stage is usually impractical and should not be attempted unless >75% of plants are infested. Control may be justified on silking-stage corn if small larvae are detected before they have tunneled into the shanks and ears. Spray should be directed toward the ear zone to target shank feeding-larvae that will cause ear droppage. Chemigation, where the label allows, may improve the performance of some products. Note that corn hybrids with Herculex I insect protection and some other hybrids are resistant to fall armyworm damage.

Please consult the most recent Corn Management Guide for control options.

Page last updated 3/28/2024 by J.P. Michaud.