Cooperative
Extension
Service


University of Illinois
at
Urbana-Champaign


No. 1/March 19, 1998

Insect Management Issues for 1998

So much is happening in the world of insect management that each new yearpromises exciting developments and challenges. As this season begins, you andwe alike are asking many questions about what to expect this year. Bt -corn will be planted on significantly more acres in 1998 than in 1997, butwe don't know whether economically threatening densities of European orsouthwestern corn borers will develop. Will corn borers have a heyday again asthey did in 1997, or will weather conditions and natural enemies conspire toreduce their survival? Will growers plant non-Bt refuges to contributeto the longevity of this exciting new technology, or will they ignore advicefrom universities and industry alike and plant Bt -corn fence post tofence post? (At least one individual is suggesting that Bt -corn will bethe solution to a myriad of problems, including hypoxia, so we should plant iteverywhere--more on this foolish suggestion in a forthcoming issue of theBulletin.) What will we learn as we continue our statewide monitoring effortsin search of corn borer larvae surviving in Bt -corn fields? Obviouslywe don't have answers to all these questions now, but we will keep youapprised of all that develops during the year, including new researchfindings.

The other "hot-ticket" insect management issue this year is the status of theproblem with western corn rootworms' causing damage in corn planted aftersoybeans. Although we probably had witnessed early signs of development ofthis problem as long ago as 1987, we discovered the severity in east-centralIllinois only three years ago (1995). With all the research activity under wayand the level of recognition of this problem among corn growers throughout thestate and elsewhere in the Corn Belt, we all are wondering what 1998 willbring. Will the problem spread in Illinois as it seems to have spread acrossnorthern Indiana and into Ohio and Michigan? Will our preliminary thresholds(two to seven adults per Pherocon AM trap per day) developed from one cycle ofdata hold up in 1998? What will our root digs reveal this summer? Will wewitness even higher densities of corn rootworm adults than we did in 1997? Allthe questions associated with this unique problem are nerve-wracking.

And speaking of rootworms, we are certain that many growers are concernedabout whether or not their soil insecticides will work this year. The rash ofpoor performance of soil insecticides in 1997 has left many folks with thefeeling that soil insecticides may not be as reliable they thought. As we haveindicated in the past, we still feel relatively comfortable with the trackrecord of most of the soil insecticides, but they are not bulletproof. Arepeat of the conditions we experienced in 1997 would place a strain on theperformance of soil insecticides again. However, a different set ofcircumstances could allow soil insecticides to perform as they should. Andwith the new product, Regent, on the market this year, many people arewondering how it will perform. Time will tell.

All these issues and the standard concerns about black cutworms, wireworms,corn leaf aphids, bean leaf beetles, alfalfa weevils, potato leafhoppers, andmaybe even some more southern corn leaf beetles should make 1998 a veryinteresting year. As it all unfolds, we'll be here to offer our insight.
Kevin Steffey (ksteffey@uiuc.edu) and Mike Gray (m-gray4@uiuc.edu), ExtensionEntomology, (217)333-6652