Winged aphids are still on the move in Iowa, although most fields still remain well below treatment levels. Neighboring states have notable aphids, so scouting should still continue.
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.
Drs. Matt O'Neal and Erin Hodgson discuss current soybean aphid activity around Iowa and the region. Numbers are remaining low with some regions declining in density. They also discuss upcoming field tours (available at www.aep.iastate.edu).
Hot weather isn't favorable for soybean aphid, so numbers are still down. But spider mites and other pests thrive in these conditions.
Dr. Hodgson and O'Neal talk about the preharvest intervals for those soybean growers considering an insecticide late in the season.
Soybean aphids have been found on soybeans. We discuss what this might mean for management. We also report on yet another invasive insect pest of soybeans that has been found in the US, the kudzu bug.
Drs. O'Neal and Hodgson summarize reports from around the midwest and Iowa about the soybean aphid. Despite the lack of aphids in the fall, evidence so far is that they survived and are beginning to build up in the northern parts of Iowa. Numbers are still very low and do not require insecticides, but we compare 2011 to previous growing season.
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.
We discuss the likelihood that aphid outbreaks will occur and when to spray aphid populations. Some agri-businesses are suggesting that aphids be sprayed when populations are lower than 250 aphids per plant. We discuss the value of such lower thresholds, as well as ways to detect other invasive insect pests of soybeans.
Aphid populations continue to increase in Iowa. We discuss their trajectory and when/if insecticides will be needed. Also, new publications from Iowa State University are available for the soybean aphid and the brown marmorated stink bug. To purchase the id guide for stink bugs or the new soybean aphid field guide visit the ISU extension publication store (www.extension.iastate.edu/store). To learn where the brown marmorated stink bug is in Iowa visit www.ncipmpipe.org.