Monsanto will be facing stricter rules for pesticide

Minnesota is clamping down on a troublesome pesticide developed by Monsanto that brought a cascade of complaints and damaged an estimated 265,000 acres of soybeans in the state this year. Monsanto is pushing back, questioning how the state came up with the tougher standards and warning that they could be counterproductive.

At stake are millions of dollars in potential sales for the new product, both in Minnesota and nationally. Minnesota ranks third in the nation for soybean production after Illinois and Iowa, and the state’s crop was valued at $3.6 billion in 2016.

Monsanto developed a new formulation of an old pesticide, called dicamba, to solve a vexing problem: Many weeds have become resistant to Roundup and other popular weed killers, and growers and crop protection businesses are anxious to have a replacement.

So Monsanto engineered soybean and cotton seeds to tolerate the herbicide dicamba, and then created a new formulation of the herbicide called XtendiMax to kill weeds.

The problem is that dicamba is hard to control, and it drifts or volatilizes and spreads to kill soybeans and other crops on nearby fields that are not immune to the herbicide.

Farmers across the country have complained of damage. Minnesota received 250 complaints of damaged soybeans and other crops, said Gregg Regimbal, pesticide manager for the state Department of Agriculture.

“We’ve never seen numbers like that — never,” he said. Normally, there would be about 100 complaints for all pesticide products in a year.

Because of the complaints, Minnesota Department of Agriculture Commissioner Dave Frederickson issued new restrictions earlier this month for using dicamba in 2018. Growers may not use the herbicide after June 20 or on any day when temperatures are forecast to be higher than 85 degrees.

Individual states have authority to issue rules for pesticides that are more restrictive than federal requirements.