August 15, 2013
Tom Hunt, Extension Entomologist at the Haskell Ag Lab, Concord: Although weather is favorable for soybean aphid build-up, we have not observed or heard of significant populations in Nebraska (except those in my plots where I artificially infested in late July). This is likely because we did not have many to begin with.
Populations were extremely low when the weather turned unseasonably cool. Having said that, we still have time for aphids to build to economically damaging populations. We have had fast building populations in the past that developed in mid to late August, peaked the end of August, and resulted in 20% yield loss. Continued scouting is recommended. My general thought is we will not have too many problems, but each field/area can be different, so stay vigilant until soybeans are well into R6.