Don't waste your money on using putting an insecticide down with soybean seed to control soybean aphids.
North Dakota State University research indicate that a well-timed foliar insecticide applied at the economic threshold is the best pest management strategy to optimize control of soybean aphid and prevent unnecessary repeated insecticide applications, says Janet Knodel, NDSU extension entomologist.
The foliar insecticide applied at ET generally had higher yield and was the most economical treatment in the trials.
Seed treatments may have some early-season control of aphid infestation only when infestation occurs early in the season (June), Knodel says. However, peak soybean aphid infestations typically occur later in the year (late July or early August) in North Dakota.
However, insecticide seed treatments are effective in controlling other early season pests of soybeans, such as wireworms, seed corn maggots and overwintering bean leaf beetles.