"An estimated 650,000 acres of soybeans have been damaged by dicamba in Arkansas this summer and dicamba complaints filed with the state have increased at a clip not seen since 2017," Stephen Steed reports for the Arkansas Democrat-Gazette. "The estimate by the University of Arkansas System's Division of Agriculture is based on the collective experiences of extension agents, weed scientists and crop consultants who have been inspecting soybean fields across the state's eastern third the past few weeks."
Arkansas isn't the only state seeing the issue. Iowa State University field agronomists reported that they've frequently seen or heard about herbicide injury in soybeans this month, Gil Gullickson reports for Successful Farming. Though there was no statewide damage estimate, agronomist Joel DeJong said cupping—a sign of dicamba damage—was common in about 40 percent of soybean acres in Iowa, whether organic or conventional crops.
The deadline for dicamba spraying was June 30. ISU extension weed specialists said they had hoped the new federal warning label for it would help reduce dicamba damage, but the unusually hot weather may have contributed to more problems, Aaron Viner reports for Iowa Farmer Today.
"It’s difficult to imagine that we are ever going to get to a point when we are using volatile herbicides in the heat of the summer that we are not going to see issues of off-target movement by volatility," University of Illinois extension weed specialist Aaron Hager told Viner. "You can be as careful as you want as an applicator and make the application according to label guidelines, but two days later if that material starts to volatilize, it’s going to move."Meanwhile, the owner of the world's largest private seed company warned that it's too early to know the extent of dicamba damage. In an email to Gullickson, Harry Stine of Iowa-based Stine Seed Co. wrote: "The dicamba damage frequently does not show up for approximately two weeks after volatilization and moves long distances in every direction from the point of application. . . . Therefore, it is often difficult to determine if the drift is coming from a dicamba application to corn, cotton, or soybeans."