JEFFERSON CITY, Mo. (DTN) -- Just two weeks after EPA granted new labels for three "over-the-top" (OTT) dicamba herbicide products for postemergence weed control in soybeans and cotton, a group of environmental and conservation groups filed a lawsuit on Feb. 20, challenging the agency's decision.

In a petition filed with the U.S. Court of Appeals for the Ninth Circuit, the groups alleged that EPA violated its statutory duties under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and the Endangered Species Act (ESA) when granting the new use registrations for the herbicides. They have requested that the registrations be vacated.

The lawsuit was filed by the National Family Farm Coalition, the Center for Biological Diversity, the Pesticide Action & Agroecology Network and the Center for Food Safety.

"EPA's reregistration of dicamba flies in the face of a decade of damning evidence, real world farming know-how and sound science, and, oh-by-the-way, the law," said George Kimbrell, legal director of Center for Food Safety and counsel in the case, in a press release announcing the litigation. "In reality, the Trump administration has once again betrayed farmers and poisoned the environment to pad corporate pesticide profits. We will see them in Court."

This marks the fourth time since 2016 that registrations of OTT dicamba products have been challenged in court. Previous legal efforts led to federal courts vacating product registrations in both 2020 and 2024.

"(EPA Administrator) Lee Zeldin's hollow promises that new restrictions on dicamba will prevent damaging drift to nearby farms and backyard gardens is totally unsupported by the facts or common sense," said Nathan Donley, environmental health science director at the Center for Biological Diversity, in the press release. "Zeldin insists he's working closely with the Make American Healthy Again movement to make pesticides safer. But his reckless reapproval of this dangerous, highly toxic pesticide shows his words to be nothing more than an attempt to 'MAHA-wash' the facts. No one in the healthy foods movement has been fooled by Zeldin's pro-industry spin game."

In its new registrations of BASF's Engenia, Bayer's Stryax (previously called XtendiMax) and Syngenta's Tavium, EPA eliminated cutoff dates and crop growth stages that were previously used to govern application of the herbicides. Instead, the labels established application requirements based on maximum air temperature, including a limit on treated acres at certain temperatures and the prohibition of application when the temperature reaches 95 degrees Fahrenheit.

A single use maximum application rate of 0.5 pounds acid equivalent of dicamba per acre was established, with a maximum annual application of 1 pound acid equivalent of dicamba per application site. The new labels also require the use of approved drift-reduction agents and pH-buffering volatility reduction agents.

DIFFERENT PERSPECTIVES

When announcing its decision to approve new labels, an EPA stated that it had "established the strongest protections in agency history for over-the-top (OTT) dicamba application on dicamba-tolerant cotton and soybean crops." The groups suing the agency presented a different perspective, claiming the herbicides' approval "substantially loosens previously weak restrictions the pesticide companies proposed when they applied for dicamba reapprovals in 2024."

"This is deja vu all over again," said Jim Goodman, president of the National Family Farm Coalition, in the groups' press release. "Despite an extensive history of failed weed management in genetically engineered crops, thousands of complaints by farmers about crop damage caused by drift, and two prior court bans, EPA is once again reregistering dicamba. There is no rationale for reapproving this incredibly harmful herbicide other than to line the pockets of the agri-chemical industry. National Family Farm Coalition is standing up for family farmers and rural communities everywhere in urging our courts to block this egregious, irresponsible and unjust reapproval."

CONCERN OF PITTING FARMER AGAINST FARMER

"Dicamba's tendency to volatilize and drift is well-documented and when dicamba was registered for over-the-top spraying, our vegetable farm, like so many farms, saw a significant decline in marketable produce from damage," said Rob Faux, an Iowa farmer and communications manager at Petitioner Pesticide Action & Agroecology Network. "Successful legal challenges removed dicamba's prior registrations, and because of that we have had successful seasons without dicamba drift. A new dicamba registration will, once again, pit farmer against farmer, and some of us will be forced to exit food production."

In reply to a DTN request for comment on the latest litigation, a Bayer spokesperson stated, "We stand behind the EPA, and the thorough, science-based review process the agency has completed. Dicamba is a vitally important tool for U.S. farmers."

An EPA spokesperson told DTN that the agency wanted to provide a comment but needed more time. A spokesperson for Syngenta told DTN the company had no comment to provide at this time. DTN also reached out to BASF and the American Soybean Association for comment but did not receive immediate responses.

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Jason Jenkins can be reached at jason.jenkins@dtn.com

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