It's Not Too Late for European Corn Borers

August 6, 1999
Although European corn borers have been almost eerily absent from most cornfields this year, it's not too late for moths laying eggs for the second generation to seek out fields, especially late-planted fields, for oviposition. A recent surge of captures of moths in a light trap in Warren County should be of interest to you. Carol Parrish and Brian McMillen at the Monsanto Agronomy Center near Monmouth, Illinois, have been using blacklight traps to monitor corn borer moth activity all season. Captures of moths in their trap from July 14 through 23 were relatively low. However, the numbers increased noticeably on July 26 and 28. The numbers jumped up to 31 and 50 moths per trap per day on August 2 and 4, respectively. Although these numbers are not extremely large, they are significantly larger than moth captures they reported at any other time during the season.

European corn borer moths.

As we have done in the past, let's all drive around on country roads at night and watch for the splatter marks on our car windshields. However, keep in mind that other moths like to paint your windshields, too. Don't assume that the splats are corn borer moths; stop and identify them accurately. Female corn borer splats are yellow-tan; male corn borer splats are darker and more olive in color. Also remember that the shapes and sizes of the splats depend largely on the speed at which you are driving when the scouting impact occurs. Splats obtained during a drive along an interstate are significantly less identifiable than those obtained during leisurely drives through the country.

Egg mass of second-generation European corn borer.

If you are monitoring European corn borer moth flights and/or scouting for egg masses, let us know what you find.--Kevin Steffey

Author: Kevin Steffey