University of Illinois

No. 8/May 16, 1997

What's the Status of European Corn Borers?

Information presented in volume 7, no. 5 (May 2, 1997), of the University of Missouri's Integrated Pest and Crop Management newsletter indicates that European corn borer moths could be observed by May 19 in southern Illinois and by May 20 as far north as Springfield. I extrapolated from their sites in Missouri. The dates are based upon heat units accumulated from April 1, 1997, to ignore early season temperatures above a base of 50 degrees F that apparently do not affect development of corn borers significantly. Although the projected date for appearance of corn borer moths in the Springfield area seems a bit early, especially this year, it's probably not too early for folks in southern Illinois to begin watching for corn borer moths at night. If they do emerge this early, it's likely that the corn will not be tall enough to support infestations of first-generation corn borers. Stay tuned.
Kevin Steffey, Extension Entomology, (217) 333-6652