Little pockets of soybean aphids are starting to pop up in the SE area of North Dakota. Low densities of soybean aphids and <1% of the plant infested were observed in Cass County near Harwood, Grand Forks County near Emerado, and Ransom County near Lisbon.

Scout fields for this yellowish-green, tiny (about ¹/₁₆ inch long) pear-shaped aphid with two black cornicles. They are commonly found feeding on the underside of the leaf and in the top ‘tender’ leaves of vegetative soybeans. Look for predators like lady beetles, lacewing larvae, syphrid fly larvae as signs that soybean aphids are present since they prey on aphids. However, it is early and lots of thunderstorms are in the forecast, hot temperatures, which can wipe out aphid colonies fast!  Stay tuned and please share your soybean aphid field reports with me.

Janet J. Knodel

Extension Entomologist