For a second growing season in a row, Minnesota soybean growers cannot use the herbicide dicamba after June 20, the Minnesota Department of Agriculture announced last week.
The state-specific restriction, which the agency set in 2018 and again for the 2019 growing season, is in addition to those announced Oct. 31 by EPA for the 2019-2020 growing seasons:
• Only certified applicators may apply dicamba over the top. Those working under the supervision of a certified applicator may no longer make applications.
• The restriction prohibits over-the-top application of dicamba on soybeans 45 days after planting.
• Over-the-top applications on soybeans remain at two applications.
• Applications will be allowed only from one hour after sunrise to two hours before sunset.
• In counties where endangered species may exist, the downwind buffer will remain at 110 feet. There will be a new 57-foot buffer around the other sides of the field. The 110-foot downwind buffer applies to all applications, not just in counties where endangered species may exist.
• MDA issued enhanced tank cleanout instructions for the entire system.
• MDA issued an enhanced label to improve applicator awareness on the impact of low pH on the potential volatility of dicamba.
• Labels went through a cleanup and consistency process to improve compliance and enforceability.
Training periods for 2019 and beyond will be clarified, ensuring consistency across all three dicamba products: XtendiMax by Monsanto, Engenia by BASF, and FeXapan by DuPont.
MDA’s decision to stick with the June 20 cutoff date was based on investigations, input from the Minnesota Soybean Growers Association Drift Task Force, the University of Minnesota Extension weed scientists, pesticide manufacturers, and informal surveys into reports of crop damage from alleged dicamba off-target movement over the past two growing seasons, according to a MDA news release.
Also, there will be no temperature application restriction in 2019.
In 2017, MDA received 253 reports of alleged dicamba drift. Fifty-five of those were formal complaints requesting investigations. Those reports affected an estimated 265,000 acres.
After state restrictions were put in place for the 2018 growing season, the number of complaints dropped dramatically to 53 reports, of which 29 were formal complaints. Just over 1,800 acres were affected in 2018.
“We now have two years’ worth of data to show what measures can and should be taken to limit the potential drift of dicamba to nontarget crops,” said Dave Frederickson, ag commissioner. “It is evident that measures put in place last year worked well, and we must continue to use this product in a prudent manner.”
The majority of 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.
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.
For more information on EPA’s decision on dicamba, visit EPA’s dicamba registration page.