By now almost everyone has heard about dicamba, the volatile growth regulator herbicide that has garnered so much attention the past couple of years. It is being used over the top of dicamba-tolerant soybeans on thousands of acres in the state this year. We are trying to keep track of off-target damage so we would like to hear from growers that see any typical symptoms. Grapes are one of the most sensitive crops to dicamba, though there is a wide range of sensitivity among varieties. But they are not the only fruit crops that are sensitive. Raspberries, blackberries, blueberries, and tree fruit are also sensitive. Dicamba typically causes upward leaf rolling on new growth (see pictures below). If you see this type of damage in your fruit plantings, please contact your local Purdue Extension Educator or one of the specialists that write this newsletter. The more we know about the extent of damage, the better we can advise regulators on reducing off-target movement.
Typical upward leaf rolling on new grape growth indicative of exposure to dicamba herbicide
Dicamba damage in black raspberry
Dicamba damage on Ouachita blackberry