Duane Frederking, field sales agronomist with Pioneer Hi-Bred International, and Matt Montgomery, Sangamon/Menard Extension unit educator in crop systems, reported encountering "clouds" of European corn borer moths in grassy areas around cornfields in Cass, Menard, Morgan, and Sangamon counties. Duane's windshield apparently "got plastered" with corn borer moths during a recent drive home at night. They also found some egg masses on some of the corn plants during the week of May 3. The plants they examined were in the 6- to 7-leaf stage. Ria Barrido, an agronomic systems manager with Monsanto Company, found European corn borer egg masses on 4- to 5-leaf-stage corn in Douglas County on June 7.|
In last week's Bulletin (issue no. 11, June 7, 2002), Mike Gray wrote a detailed article about European corn borers. He and others have observed quite a mixture of corn plant heights across the state. Consequently, the differential corn heights probably will have an impact on survival of this first generation. As we have indicated several times, European corn borer larvae probably will not survive very well on plants less than 16 inches tall (higher levels of DIMBOA). However, if the larvae become established on taller plants, the infestations in west-southwestern Illinois could be significant. Although we have not received reports about European corn borers from elsewhere in the state, we urge people throughout the state to start looking, especially in early-planted fields.
We have become aware of an irresponsible recommendation from an independent consultant in Illinois. Apparently he has recommended application of an insecticide for control of European corn borers on corn that is spiking to 12 inches tall. We cannot fathom the rationale for this recommendation, but we strongly oppose it. This type of recommendation takes advantage of the frustration that a lot of farmers have had with poor planting and growing conditions this spring. Applying an insecticide to corn on which corn borer larvae probably will not survive is a waste of money. We would appreciate your help in contradicting such inappropriate recommendations.
To our readers in northern Illinois, please let us know when you begin to observe European corn borer adults, egg masses, or larvae. Corn in northwestern Illinois was planted relatively early compared with planting times elsewhere in the state, so infestations of corn borers could be significant. Your reports to use will enable us to spread the word.
Refer to last week's Bulletin (issue no. 11, June 7, 2002) for information about scouting, making control decisions, and insecticides suggested for control of European corn borers.--Kevin Steffey and Mike Gray