University of Illinois

No. 9/May 22, 1998

Black Cutworms: More Reports on Pinhole Feeding on Leaves

General reports of pinhole leaf feeding caused by black cutworm larvae are common in many areas of the state. Observations of some cutting activity also have been reported in widely scattered areas of Illinois. We have provided numerous tips in previous issues of this Bulletin regarding scouting procedures, economic thresholds, insecticide efficacy, and potential yield-loss relationships for black cutworms. Don't underestimate the potential influence that black cutworms can exert on a stand of corn. Corn fields at the 4-leaf stage or below remain at economic risk to cutworm infestations. Bottom line--look for early signs of leaf feeding, and be prepared to rescue certain fields where economic infestations of black cutworms are thinning stands.

Mike Gray, (, Extension Entomology, (217)333-6652