In last week's issue of the Bulletin (no. 19, August 4, 2000), I suggested that you should continue watching for European and southwestern corn borers, especially in later-planted cornfields. Although the flight of southwestern corn borers laying eggs for the second generation has peaked, I told you that the counts from traps in southern Illinois (as reported by Ron Hines, senior research agronomist at the Dixon Springs Ag Center) were extremely large this year. Alan Mosler with Twin Counties FS indicated on August 4 that second and third instars were present throughout southern counties and that boring into stalks was imminent.
For the rest of the state, it's worth noting that European corn borer adults are rather common. I continue to see them every night, either in my yard or flying into my house, and others have reported considerably larger numbers than they had seen earlier this year. I heard one report that a light trap at the Monsanto farm near Monmouth in Warren County had captured more than 600 moths (I don't know the number of nights over which this capture took place). I have also heard of small pockets of significant infestations in several areas of the state. We may be in for a few surprises this fall when we conduct our annual survey.
Let us know what you have found in your region the past couple of weeks. We'd like to get a better feel for the ranges of percentage of infestations and the locations of infestations.--Kevin Steffey