Federal court bans use of three dicamba weedkillers

Soybean pods appeared to be filling out nicely in Portage County, Ohio on September 1, 2022. (Farm and Dairy file photo)

SALEM, Ohio — A federal court in Arizona recently banned three widely used dicamba-based weedkillers, after finding the Environmental Protection Agency broke the law by allowing them to be on the market.

The decision will impact three of the world’s biggest agrochemical companies — Bayer, BASF and Syngenta — who are accused of knowingly selling weedkillers that have damaged millions of acres of crops and caused harm to wildlife and the environment.

Environmental groups praised the decision, while some farmers expressed concern for the upcoming spring planting season. Because of the timing, the EPA said farmers will be able to use “existing stocks” of dicamba.

“We are grateful to EPA for hearing farmers’ and ranchers’ concerns and addressing them quickly to ensure we have access to the critical tools needed to protect our crops this season,” said Zippy Duvall, American Farm Bureau Federation president, in a statement. “Without EPA stepping in, farmers and ranchers across the country were facing uncertainty and financial risk.”

Case details

In December 2020, farmers and conservations groups filed a lawsuit claiming the EPA’s approval of Bayer’s XtendiMax, BASF’s Engenia and Syngenta’s Tavium weedkiller had violated two laws: the Federal Insecticide, Fungicide and Rodenticide Act and the Endangered Species Act.

Documents in the lawsuit cited the EPA rushed the 2020 decision and that scientists did not have enough time to do a proper analysis of the weedkillers.

Five years later, on Feb. 6, the U.S. District Court of Arizona ruled the EPA made a crucial error in re-approving the product as the EPA didn’t post it for a public notice and comment period as required by law.

In a 47-page ruling, U.S. District Judge David Bury wrote the EPA made a “very serious” violation and that if they did do a full analysis, they wouldn’t have made the same decision.

Case background

The recent federal court ruling marks the second time a court has banned the use of dicamba-based weedkillers since the latest formula appeared on the market in 2017.

The first time was in 2020 by the Ninth Circuit Court of Appeals, however, a few months later, the Trump Administration reapproved the products.

Dicamba-based weedkillers will no longer be sold on the market, however, farmers will still be able to use “existing stocks” — products purchased and shipped before Feb. 6 — and products already in the possessions of owners can be re-distributed within a set of EPA guidelines.

American Soybean Association President Josh Gackle, commended the EPA’s decision to allow farmers to use dicamba weedkillers purchased before the deadline for the upcoming growing season.

“This ruling potentially affects more than 50 million acres of dicamba-tolerant soybeans and cotton — an area larger than the state of Nebraska — we are very appreciative of EPA’s decision to let us get through the 2024 growing season by using any product already in the delivery pipeline,” said Gackle.

In a statement, Bayer said it disagreed with the court’s ruling: “Our top priority is making sure growers have the approved products and support they need to safely and successfully grow their crops.”


Dicamba was first introduced to U.S. agriculture in 1967. However, the chemical was not widely used during the warm months as it was known to volatilize and drift long distances when it was hot.

Companies like BASF and Monsanto eventually updated their formulas to eradicate this flaw in dicamba. The EPA approved the latest version of dicamba-based weedkillers for the 2017 growing season.

Despite the updated formula, in December 2021, the EPA found dicamba was still drifting away from where it was applied.

Since 2017, evidence also came out indicating Monsanto and BASF knew its use would result in damage. For years, BASF and Bayer blamed crop damage on the use of the older, illegal dicamba weedkiller. In response, the EPA and states have added new restrictions every year — which Bury wrote wasn’t working.

Millions of dollars worth of crop damage and numerous lawsuits have taken place as a result of the weedkillers.

In February 2020, a Missouri federal judge ordered Bayer and BASF to pay Missouri’s largest peach farmer $265 million worth of damages to his farm. The total was later reduced and the companies each paid $15 million in compensatory damages.

In June 2020, Bayer also provided soybean growers with a $400 million settlement for non-target drift. According to EPA statistics, dicamba-resistant crops have been planted on roughly 65 million acres.

(Reporter Liz Partsch can be reached at epartsch@farmanddairy.com or 330-337-3419.)


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