For the past 5 years, we have evaluated insecticides for managing soybean aphids. The most recent report can be found at our website www.soybeanaphid.info. After applying insecticides as part of our 2009 insecticide evaluation, Erin and I discuss some issues to consider when selecting an insecticide
Erin and Matt report on observations on aphid populations around Iowa from the week of August 3-7. We discuss the continued production of winged aphids, their capture in the suction trap network (visit it at www.ncipm.org/traps/), and the changing appearance of aphids in the field (winged, wingless and white dwarves). If you have questions, please post them at www.soybeanaphid.info.
Erin and Matt discuss the recent increase in aphid populations including winged aphids that are moving from field to field. We discuss what growers should consider when applying insecticide to soybeans when seeds are developing. We summarize a recent Integrated Crop Management newsletter articles on late season management of soybean aphids. For more information visit www.extension.iastate.edu/CropNews/2009/0813hodgsononeal2.htm
Its mid-August and soybean aphids are starting to look white and small (yes, even smaller). Do they count? Are aphid populations still increasing? Why? Erin and Matt answer these questions and more.
Have a question about aphids or other insect pests? Visit www.soybeanaphid.info and post a question.
Matt O'Neal talks with Amy Asmus of Asmus Farm Supply to discuss outbreaks of aphids in cornfields around north-central Iowa. The two discuss what species of aphids are in corn and what impact they may have. Be prepared for more questions than answers as the scientist and crop consultant compare notes about this problem. For a more complete description of the aphids see Dr. Erin Hodgson's article in the Integrated Crop Management Newsletter (www.extension.iastate.edu/CropNews/2009/0807hodgson.htm)
Dr. Mary Gardiner, assistant professor at the Ohio State University, visited ISU and gave a seminar about her research on the ladybeetles. Ladybeetles can play a positive role by feeding on pest like the soybean aphid. Mary's research is focused on the exotic multi-colored asian ladybeetle. This species is a voracious predator of soybean aphids, but is also a pest in our homes and to grape growers. Mary is documenting the role landscape plays in the establishment of this species as part of her Buckeye Lady Beetle Blitz. To learn more about Mary's work visit http://ladybeetles.osu.edu/default.asp
Soybean aphids are picking up activity throughout Iowa; however, populations are still very patchy. Also consider other defoliators in soybean right now that might compound stress during pod set.
We share reports of aphid outbreaks in soybeans in MN. Numbers are up in Iowa. Also, have you noticed big, metallic green beetles? Japanese beetles are out in Iowa.
As soybeans reach the late reproductive stages the need to manage aphids decreases. However, aphids persist in soybean fields around the midwest. We discuss a couple factors that should be considered when applying insecticides this late in the year. Also, we re-count the spread of Japanese beetles in Iowa as a new herbivore of soybeans.
We are getting close to the end of the season and soybean aphids have exceeded the threshold level in northern Iowa. Erin has come back from spraying research plots to share with us updates on timing, product choice and assessing the need for an insecticide during this aphid outbreak.
Also, Matt is going to be interviewed by WHO-TV this Friday. Look for a segment either Friday nite or during the weekend (23-25 Aug) about conserving bees.And finally, this episode is dedicated to Robert Pettis, our #1 fan.