Common Name: Corn earworm
Scientific Name: Noctuidae: Heliothis zea
Status: A pest of corn, particularly sweet corn
Damaging Stage: Caterpillar

Biology: Adult moths are light-yellow and have distinctively different color patterns in the underwings. Larvae can be light green, pink, dark brown or nearly black. They have alternating light and dark stripes that run longitudinally down the body. Usually, there are double dark stripes towards the center of the back. When mature, larvae reach a length of approximately 1 � inches. There are usually two to three generations per year.

Injury: After eggs hatch, the larvae feed on leaves, tassels, the whorl and within ears. Most of the damage inflicted is on the ears since it is the preferential site for corn earworms. Extensive damage is characterized by large amounts of frass around the ear tips. The younger larvae feed on the corn silks, clipping them off.

Action Threshold: Treatment is required if 5-10% of the corn plants are infested.

Management: Corn earworm can be regulated with cultural and biological controls. Chemical treatments, if applied too late, are not effective. Larvae that have already tunneled into the corn ear are protected from insecticide applications.