Factsheets from Pennsylvania State University Cutworm. Cutworms are among the most difficult insect pests of corn to control. The insect overwinters as pupae in the soil and also as adults. Some adults may fly in from southern areas of the United States. Eggs are deposited in April and May, usually before the crop is planted.
Adults tend to be attracted to trashy fields or fields where green weeds are present.
Newly hatched larvae feed on the weeds until new corn seedlings emerge. When larvae are small, their feeding may go unnoticed. If the soil is moist, cutworms cut the plants off just above ground level. The cutworm develops from egg to adult in approximately 2 months. If the majority of larvae are 1.5 to 2 inches long, control does not help because most of their feeding is complete.