Four public interest groups filed a lawsuit challenging EPA's five-year registration for dicamba. Soy and cotton growers filed their own lawsuit in November actually challenging the extra restrictions required by EPA, while the latest case says EPA doesn’t go far enough in controlling drift concerns.  

In October, EPA registered dicamba for use on dicamba-tolerant soybeans and cotton under the Federal Insecticide, Fungicide, and Rodenticide Act. The soy and cotton growers’ lawsuit claims some aspects of the registration decision including buffer requirements and application cutoffs are “problematic for growers, who depend on reasonable, consistent access to dicamba for use on DT soybeans and cotton.”

The new lawsuit follows the groups’ successful prior cases, decided in June, in which the court ruled the EPA’s previous approval to be unlawful and struck it down. Plaintiffs include the Center for Biological Diversity, Pesticide Action Network North America and the National Family Farm Coalition.

“Less than six months ago, the Ninth Circuit resoundingly rejected Monsanto’s and EPA’s arguments about this pesticide, detailing its substantial drift harms,” says George Kimbrell, legal director of Center for Food Safety and counsel in the case.

As the latest lawsuit explains, the EPA again “failed in its legal duties to ensure that the pesticide would not cause unreasonable harm to farmers and farming communities as well as to the environment and hundreds of endangered species.” CFS says.

In its June 2020 56-page decision, the court explained that the EPA violated the law when it failed to consider and account for the “enormous and unprecedented damage” caused by dicamba drift — damage that has "torn apart the social fabric of many farming communities.” This is the third time the agency has registered these products, each time with additional restrictions that have failed to stem devastating drift, the groups say.

“We’re in court yet again because for four years the EPA has repeatedly claimed dicamba is safe, and for four years the agency has been dead wrong, resulting in millions of acres of damage,” said Nathan Donley, a senior scientist at the Center for Biological Diversity.

Kristin Schafer, executive director of Pesticide Action Network North America, a plaintiff in the case, adds, “Millions of acres of crops have already been damaged by dicamba. This herbicide is hurting farmers and is already creating more resistant weeds, accelerating a dangerous pesticide treadmill.”

As part of the efforts to address the concerns outlined to address the June U.S. Court of Appeals for the Ninth Circuit decision, new mitigation requirements include a national cutoff date of June 30 for soybeans and July 30 for cotton for all over-the-top applications of dicamba. In addition, EPA is also requiring the mixture of pH-buffering agents (also called a Volatility Reduction Agent) already available on the marketplace to minimize the volatility of the compound. The registration process also requires a downwind buffer of 240 feet, and in any region covered by the Endangered Species Act a 310-foot buffer.

The grower lawsuit states, “In particular, several registration conditions impose growing restrictions and disrupt growing seasons which will diminish crop yields, cut productivity, and drive up operational costs. Some of these conditions are significantly more stringent than those found in past dicamba registrations.”

An estimated 64 million acres of dicamba-tolerant seed was planted in 2020. Weeds alone pose a greater threat to soybeans than either insects or diseases, and independently drive soybean yields down 37% worldwide. Experts estimate that, without herbicides, weeds would cut soybean yields in half, notes the American Soybean Association in the farm group lawsuit.