Spring wheat is advancing quickly with 74% jointed, 30% boot and 10% headed (Source: North Dakota Crop, Livestock and Weather Report, USDA NASS, June 11, 2012).
However, spring wheat and other cereal crops are still susceptible (up to the completion of heading) to yield loss caused by cereal aphids. High populations were observed by the NDSU IPM scout in Sargent and Ransom Counties this past week.
Bruce Potter, IPM Specialist, also found fields with very high aphid populations (sticky with honeydew that the aphids excrete) in WC and SC Minnesota. Although hot spots are spotty, continue to scout cereal crops for aphids.
Some fields also have high populations of beneficial insects (such as, lady beetles, green lacewings, syrphid flies, parasitic wasps) and aphid populations are decreasing! The economic threshold is when >85% of the stems have one or more aphids.