Two male adult soybean gall midges were found in emergence cages at the Northwest Research and Demonstration Farm near Sutherland on June 6. This is about one week earlier than previous first captures in Iowa since we started monitoring emergence in 2019. The first Midwest report of soybean gall midge emergence in 2023 was May 31 near Mead, Nebraska. You can keep up with soybean gall midge emergence at soybeangallmidge.org/. We will also send text updates on soybean gall midge activity in Iowa through the Iowa Pest Alert Network this summer.
Typically, plant injury becomes noticeable, and larvae can be found feeding within stems a few weeks after adult emergence. Begin scouting for soybean gall midge larvae now, especially if plants are at least V2. Start scouting at the edge of soybean fields adjacent to fields where soybean was grown last year. A black lesion is usually noticeable at the base of the plant (Photo 2). Look for white or orange larvae feeding inside soybean stems (Photo 3) by using your fingernail or a knife to split the stem. Early in the season, infestations might be noticeable if random plants are dead or wilting among otherwise healthy-looking plants (Photo 4). This becomes less obvious later in the season as the canopy closes.
Unfortunately, there are no known, effective management strategies to suppress larvae at this time. Universities around the Midwest continue to monitor the distribution and evaluate potential management strategies. Read more about soybean gall midge identification, biology, and scouting in this encyclopedia article.
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