Cupped, crinkled soybeans are never a sight you want to see. If you run across those symptoms this year, then know that dicamba drift could be the culprit. However, double-check plants for conditions that mimic dicamba damage. Such conditions include clopyralid herbicide injury; herbicide damage brought on by cool, wet conditions; heavy soybean aphid feeding; bean pod mottle virus; soybean mosaic virus; or dwarf virus.
Although dicamba damage in soybeans is relatively easy to recognize, it’s difficult to identify the source of spray drift and volatilization. It can take seven days to 21 days for dicamba damage to appear in a crop—and it only shows up on new leaves, not the leaves present at the time of application. As little as 0.06% to 1.9% dicamba spray drift can cause yield loss, according to North Dakota State University research.
For those farmers and applicators who apply dicamba, keep detailed records of when and where it was applied, and note wind speed and temperature at the time of application to protect yourself if drift appears in your area. If you think you might have dicamba drift damage, then contact an Extension agent who can help investigate the origin of the drift and take further action to hold the responsible party accountable. You could also consider speaking with a lawyer to recover damages.