By Tom Polansek
CHICAGO (Reuters) - The U.S. Environmental Protection Agency (EPA) said on Monday that farmers can use existing supplies of an agricultural weed killer linked to crop damage, after a federal court blocked sales and use of the product last week.
The EPA said farmers have until July 31 to use supplies of dicamba-based herbicides that they had on hand as of June 3. The products, sold by Bayer AG <BAYGn.DE> and rivals, are known to drift away and damage crops that are not resistant to the chemical.
A three-judge panel of the 9th U.S. Circuit Court of Appeals ruled on June 3 that the EPA had substantially understated the risks related to the use of the herbicides, which are sprayed on genetically engineered soybeans and cotton.
The decision confused farmers who bought herbicides months ago as they wrap up planting in the U.S., the world's No. 2 soybean exporter. Different responses to the decision from states subsequently created an uneven playing field for growers.
"EPA's order will mitigate some of the devastating economic consequences of the court's decision for growers," the EPA said in a statement.
About 60% of the U.S. soybean crop this year is expected to be seeded with Bayer's dicamba-resistant Xtend soybeans, according to Bayer. They need to be sprayed with the herbicide to ward off weeds that have developed a tolerance for another chemical, glyphosate.
Several farm states said after the court decision that they would allow dicamba spraying as they waited for guidance from the EPA. Plaintiffs in the court case against the EPA, which include environmental and public-interest groups, had urged the agency to immediately tell states that it was illegal to use the dicamba herbicides.
"Today's disingenuous order from the EPA flies in the face of the court decision holding these pesticides unlawful," attorneys for the plaintiffs said in a statement.
(Reporting by Tom Polansek; Editing by Kim Coghill, Christopher Cushing and Leslie Adler)