After about three hours of public hearings before an overflow audience, the Arkansas Plant Board on Nov. 21 passed a rule that would severely restrict the use of dicamba herbicide. The proposed restrictions now go to the governor.
The hearing was prompted by numerous reports this summer of off-target movement of dicamba illegally applied to soybeans and cotton genetically engineered by Monsanto Co. to tolerate the herbicide. Among the speakers were northeast Arkansas relatives of a man killed in October over an alleged argument with a neighbor about illegal dicamba application.
Ten other states have registered XtendiMax herbicide for use on Xtend soybeans. They are Colorado, New Mexico, Oklahoma, Minnesota, Wisconsin, Ohio, South Carolina, Delaware, New Jersey and Virginia. Four states have approved XtendiMax herbicide for use on cotton. They are New Mexico, Oklahoma, South Carolina and Virginia.
The Xtend trait, which imparts resistance to dicamba, was deregulated by the Environmental Protection Agency in 2015. But the EPA just issued a conditional registration for XtendiMax herbicide with VaporGrip Technology, a low-volatility formulation of dicamba. Each state then has to register the herbicide for it to be used legally there.
Dicamba is known for its volatility. Even when applied according to label, it can vaporize and move to neighboring crops under the right conditions. The VaporGrip technology is designed to significantly reduce that volatility and associated off-target movement, according to Monsanto.
Monsanto sold about 1 million acres of Roundup Ready 2 Xtend soybeans during the 2016 season and has plans to increase that to 3 million acres of soybeans tolerant to glyphosate and dicamba in 2017. Because the accompanying dicamba herbicide was not registered for in-season use on those crops during the 2016 season, only over-the-top glyphosate could be applied legally.
The St. Louis-based company also has plans to sell about 1 million acres worth of cotton for 2017 that has been engineered to tolerate glyphosate, dicamba and glufosinate.
In addition to the complaints received by the Arkansas Plant Board, the Missouri Department of Agriculture is investigating more than 100 reports of illegal dicamba application, mostly in the Bootheel region. The FBI also has entered into those investigations.
The Arkansas Plant Board received 245 written comments during the public comment period overwhelmingly in favor of the dicamba restrictions. Of the 245, only five opposed the restrictions.
The board unanimously approved the proposed restrictions 16-0, with two members abstaining because of conflict of interest.
The proposal includes:
• Banning dicamba herbicides of dimethylamine (DMA) salt and acid formulations, except on pastures but only if all susceptible crops are at least 1 mile away in all directions.
• Prohibiting spraying of all dicamba composed of diglycolamine (DGA) salt and sodium salt from April 15 through Sept. 15, except on pastures or rangeland, again with a 1-mile buffer. The active ingredient in XtendiMax herbicide is DGA salt.
• Requiring farmers who use a salt dicamba called Engenia, by BASF, on the new Monsanto cotton and soybeans to have a quarter-mile downwind buffer zone and 100-foot buffer in all other directions.
• Requiring anyone who uses any of the DGA-based herbicides on genetically modified seed by Dow Chemical Co. or Monsanto to be trained and certified by the state. Dow’s Enlist system includes genetically engineered corn, soybeans and cotton that tolerate over-the-top applications of 2,4-D and glyphosate herbicides. The U.S. Department of Agriculture has deregulated the Enlist traits. The EPA has registered Dow’s Enlist Duo herbicide, a premix of 2,4-D choline and glyphosate with the proprietary drift retardant, Colex-D, for use on Enlist corn and soybeans in 15 states. It is not yet registered for use on Enlist cotton.
In a separate action, Arkansas Plant Board committee earlier this summer proposed increasing fines for illegal pesticide spraying from the current $1,000 per violation to $25,000. The Arkansas Legislature would have to approve this measure.
Read more about the dicamba drift problems at A perfect storm: Deregulated herbicide trait and illegal herbicide use converge for historic drift injury to crops.”