The subject of this proposal is research and outreach on the soybean aphid, Aphis glycines. The soybean aphid is the most damaging insect pest to soybean production in North America (Ragsdale et al. 2011). The advent of soybean aphid as a U.S. crop pest in 2000 has significantly changed soybean production practices in the North Central region. 77% of soybean acreage or more are now scouted for insect pests, a 40-fold increase since the introduction of soybean aphid (Song and Swinton 2009). During past soybean aphid outbreaks as much as 57% of states’ soybean acreage have been treated with insecticide (USDA-NASS), at a typical cost between $6-$25/acre. It is also becoming routine for producers to invest $10/acre or more in prophylactic insecticidal seed treatments, though independent data are generally lacking that these treatments are cost-effective for soybean aphid management. This project is funded by the North Central Soybean Research Program (http://www.soybeanresearchinfo.com/pests/aphid.html).