By Scout Nelson
Soybean gall midge larvae have been detected infesting soybean plants in a field near Rosemount, southeast Minnesota, on July 15, 2025. This marks the first confirmed detection of this pest in Dakota County and continues its eastward expansion in the region.
The larvae were mostly found on the edge of the soybean field, next to a corn field. The infestation level was relatively low, affecting only 3.2% of the soybean plants on the edge. The affected plants showed darkened lesions at the base of their stems near the soil, which is typical of soybean gall midge damage. However, none of the plants were observed wilting or dying at this stage.
Monitoring efforts for this pest will continue both in this field and nearby areas. It is important to note that as summer progresses, particularly through August, soybean gall midge infestations tend to become more noticeable. The symptoms can increase as more plants get infected. Infested plants may start to wilt, die, or lodge, in addition to showing dark lesions.
Helpful resources, including videos by experts from the University of Minnesota and the University of Nebraska–Lincoln, offer guidance on how to scout for soybean gall midge in fields. These resources can assist in early detection and proper monitoring.
“If you detect soybean gall midge in your fields, please contact me (koch0125@umn.edu). We are interested in documenting how widespread the infestations are of this pest in Minnesota, and we need additional sites to perform research to develop management strategies for this pest.”
Researchers are keen to track the spread of this pest and gather more information to help create effective control methods. Early detection and reporting are key to understanding its impact on Minnesota’s soybean fields.
Photo Credit:istock-sandramatic
Categories: Minnesota, Crops, Soybeans