Issue No. 10, Article 6/June 1, 2007
Soybean Aphids Found in Minnesota
David Ragsdale, research entomologist at the University of Minnesota, has reported that he and his colleagues found soybean aphids on V1-stage soybeans (planted during the first week of May) in east-central Minnesota during the week of May 28. In some fields, more than 25% of plants are infested, and the average density was about 5 aphids per plant. The aphids that are beginning to colonize soybeans were likely the end result of the alatoid nymphs (nymphs that will molt into winged adults) that the entomologists observed on buckthorn before the Memorial Day weekend.
If you want to be forewarned, especially in northern Illinois, consider looking for soybean aphids as soon as possible. If the aphids begin colonizing soybeans in Illinois early this year, we could be in for a long season. Remember that finding soybean aphids early does not necessarily mean that economic infestations will develop, but forewarned is being prepared.
We will begin some surveys of soybean aphids in commercial soybean fields next week, and we will keep you apprised of our findings.--Kevin Steffey