We continue to receive reports of and inquiries about Japanese beetles in soybeans and corn. One of the questions asked most frequently is, "How much longer will these beetles be around?" The bad news is that the adults will continue to feed throughout July and August. You likely will be able to find some of the adults in September. Therefore, you can't let your guard down. As another reminder, don't overreact to the injury. I have seen some fields with considerable Japanese beetle injury at the edges but very little injury in the interior. Before making a decision to treat the entire field, scout the entire field. There is no need to spend money needlessly, especially given the current value of soybeans. |
Obviously, the critical time for scouting for Japanese beetles in corn is during pollination. After pollination is complete, Japanese beetles will not cause economic damage to corn. Watch for the beetles clipping silks.
Detailed information about Japanese beetles, including economic thresholds and suggested insecticides, was provided in issue no. 16 (July 9, 1999) of the Bulletin.
In our effort to provide added value to the Bulletin on the Web, this article contains a link to a brief video. Instructions on downloading the appropriate software and accessing the video are supplied. Let us know what you think, either positively or negatively. Feel free to offer suggestions for improvement. We have been acquiring video footage on several insect-related topics this summer, and we plan to add more video clips in time. We value your feedback, so don't be bashful.--Kevin Steffey