Minnesota Places Additional Restrictions on 2018 Dicamba Applications
The Minnesota Department of Agriculture (MDA) has placed new restrictions on the use of dicamba herbicide in Minnesota for the 2018 growing season. Dicamba is primarily used for controlling postemergence broadleaf weeds. The new restrictions are in addition to those announced by the Environmental Protection Agency in October.
The affected formulations are:
- BASF’s Engenia
- Dupont's FeXapan Plus Vapor Grip Technology
- Monsanto’s Xtendimax with Vapor Grip Technology
The decision follows MDA’s ongoing investigation and an informal survey last summer into reports of crop damage from alleged dicamba off-target movement.
Dave Frederickson, Minnesota agriculture commissioner, based the restrictions on a review of:
- New EPA label restrictions
- MDA’s survey results
- Peer reviewed literature
- Input from the Minnesota Soybean Growers Association Drift Task Force, University of Minnesota Extension weed scientists, and the pesticide manufacturers on the underlying causes of damage.
Based on the review, Frederickson set forth these additional protocols for dicamba use for the 2018 growing season:
- A June 20 application cutoff date: Setting a June 20 application cutoff date is expected to help in reducing the potential for volatility (movement), said Frederickson in an MDA news release. Most Minnesota soybeans are still in the vegetative growth stage by June 20, and research has shown that plants in the vegetative stage are less affected than those in the reproductive stage.
- An 85°F. cutoff temperature. Applications are prohibited if the air temperature of the field, at the time of application, is over 85°F., or if the National Weather Service’s forecasted high temperature for the nearest available location for the day exceeds 85°F. Research has shown that dicamba volatilization injury increases with an increase in temperatures.
“Dicamba is an important tool for soybean growers to manage weeds, and I believe these additional restrictions will minimize the off-target movement,” said Frederickson in an MDA news release. “I want to thank University of Minnesota Extension, and in particular Professor Jeff Gunsolus, for his research report on dicamba and the Minnesota Soybean Growers Association for their input on this important issue. We will be closely monitoring the herbicide’s performance with these restrictions in 2018.”
In Minnesota, the XtendiMax, Engenia, and FeXapan formulations of dicamba are Restricted Use Pesticides for retail sale to and for use only by certified applicators.