U.S. gives farmers shorter window to spray crop chemical dicamba

The U.S. Environmental Protection Agency said on Thursday it had slightly shortened the window for farmers in major soybean-producing states to use a weedkiller criticized for drifting away from where it is sprayed.

The restrictions make it harder for farmers to use dicamba, sold by agrichemical companies like Bayer AG and Syngenta, after some growers have already bought seeds and crop chemicals for spring planting.

The deadline for farmers to spray dicamba in Iowa, Illinois and Indiana will be June 12, instead of June 20 last year. The EPA approved a June 20 deadline for South Dakota, instead of June 30 last year.

The changes are intended to reduce risks, the EPA said. Some scientists consider an earlier deadline to be safer because high temperatures can increase the risk for dicamba to drift from where it is sprayed.

Farmers and scientists for years have reported problems with dicamba drifting and causing damage to nearby plants not genetically modified to resist the herbicide.

"We need an outright ban on dicamba use on genetically engineered crops because of its ongoing damage to other crops across millions of acres in the U.S.," said Nathan Donley, environmental health science director at the Center for Biological Diversity, an environmental group.

The EPA in December 2021 said it was assessing whether dicamba could be sprayed safely on soybean and cotton plants engineered to resist it, without the procedure posing "unreasonable risks" to other crops. On Thursday, the agency said it is still "evaluating all of its options for addressing future dicamba-related incidents."

Nebraska said it objected to a June 12 deadline discussed with the EPA and will keep its deadline on June 30.

"At this late date, Nebraska producers have already made their 2023 planting decisions and have likely purchased seed and pesticide products to implement their plans," said Sherry Vinton, director of the Nebraska Department of Agriculture.