Members of the Arkansas State Plant Board have approved new restrictions on a weedkiller that’s been blamed for widespread crop damage.
At the board's quarterly meeting Tuesday, members voted to require growers who use dicamba on genetically modified cotton and soybeans to keep GPS records of spraying, and to file spraying information with the board's online registry.
The board had originally considered lengthening the time period when dicamba can be sprayed by six days, but opted to keep the spraying cutoff date at May 25.
Board member Jerry Hyde of Paragould said extending the spraying window could result in more complaints of alleged damage from the herbicide.
"We had a season where it was exceptionally hot. We could have more problems with that extra week," Hyde said.
"That's correct," replied board chair Greg Hay.
The regulatory body first banned the use of dicamba in 2017, after it caused thousands of complaints of damage. The board moved the spraying cutoff date from April 15 to May 25 for the 2019 growing season after growers said the previous ban was too restrictive.
The original proposed rule, authored by Hay, would have pushed the cutoff date to May 31 and required a two mile buffer around university and USDA research stations. Hay's proposal was amended to bring it closer to the current rule, with a May 25 cutoff and one mile buffers around research stations as well as specialty and certified organic crops.
Scientists and board members voiced concern over an extended spraying season, as dicamba can become vapor at high temperatures and drift onto non-tolerant crops. So far this year, the board has received 208 complaints of alleged damage related specifically to the chemical.
Jason Norsworthy, a weed scientist with the University of Arkansas Division of Agriculture, said dicamba can exhibit volatility at relatively low temperatures when mixed with other herbicides like RoundUp.
"When you look back at the literature, at about 68 degrees you begin to see volatilization of that product and it begins to increase substantially somewhere around 80 degrees. And it's basically an exponential rise beyond by 80 degrees," Norsworthy said.
Rachel Hurley, a lawyer for dicamba manufacturer Bayer CropScience, urged members not to further restrict the chemical's use.
"We talk about hundreds or thousands of complaints, but most of them were not verified to be any of the products that you're regulating here today," Hurley said. "When you look at even how many went forward to any kind of action, it's a small amount."
The rule passed on a vote of 14 to one, with only board member Russell Black dissenting. The proposed rule goes to Gov. Asa Hutchinson for approval, then to a 30-day public comment period.
A public hearing must be held on the rule if 25 or more people or an organization with 25 or more members requests one. Following public comment, the rule must be approved by the state legislature, then by the Secretary of State before going into effect 10 days after approval.