University of Illinois

European Corn Borers at Season's End

October 9, 1998

Despite the seeming absence of economic infestations of European corn borers in 1998, several people have reported that season-end examinations of some corn fields before harvest have revealed larger-than-anticipated numbers of corn borer larvae. Although I have not heard about any significant economic infestations, some folks were caught off guard by what they found. I suspect that the borers found late in our growing season this year might have been the
result of the flurry of corn borer activity we reported in issue number 22 (August 28, 1998) of this Bulletin.

As we reported last year, we discontinued our annual fall survey for corn borers after 1996, primarily because we no longer have enough personnel and resources to maintain such a labor-intensive and time-consuming effort. However, many people have expressed interest in our historic data base of survey records from 1943 through 1996. Within the next few months, we intend to bring our data base up to date and generate graphs and/or maps that reveal
densities and infestations of corn borers in the nine crop reporting districts in Illinois. Also, we will reconsider our annual fall survey to determine whether we can find ways to resurrect it. Data from such surveys could be instrumental in helping producers make informed decisions about managing European corn borers with Bt-corn. Stay tuned.

Author: Kevin Steffey