If you grow specialty crops in Iowa or another North Central state, please help us with a study to:
The survey is at: go.osu.edu/drift12 Thank you for your help.
There is no question that dicamba injury across the Iowa landscape in 2020 is the most extensive it has been since the introduction of dicamba in the 1960s. ISUEO field agronomists and commercial agronomists in several areas of the state report nearly all non-dicamba resistant soybean are showing symptoms characteristic of dicamba, and in many fields the injury is fence row to fence row. This is not the type of injury we have observed in the past; it’s at a landscape level.
Nearly 20 years ago I summarized research from the University of Minnesota investigating factors that influence volatilization of dicamba (Behrens and Lueschen. 1979. Dicamba volatility. Weed Sci. 27:486-493). That article was prompted by an increase in off-target injury to soybean. Well, once again Iowa is suffering widespread damage to soybean from off-target dicamba movement.
Planting occurred at a near record pace in much of Iowa due to lack of rain in late April. This string of dry weather also allowed most herbicide applications to be made in a timely fashion, but now there is concern about herbicide performance after prolonged time on the soil surface.
As of July 20, the Iowa Department of Agriculture and Land Stewardship (IDALS) had received 142 cases of pesticide misuse, historically this number has ranged from 58-85 at this time of year. Dicamba was involved in 46 of these cases. Two of the dicamba cases involved use in non-crop areas, 10 involved applications on corn and 36 were related to applications to dicamba-resistant soybean (Xtend). The soybean cases were nearly evenly split between Xtendimax w/VGT and Engenia, there were no reports involving products not registered for use on soybean. Cases a
