Enlist Restrictions Eased in 10 States

USFWS Concludes Enlist Herbicides Don't Put Most Endangered Species At Risk

Jason Jenkins
By  Jason Jenkins , DTN Crops Editor
Connect with Jason:
Nearly two years after Enlist Duo and Enlist One were registered by EPA, the U.S. Fish and Wildlife Service has issued its final biological opinion on the herbicide's potential risk to endangered species. (DTN file photo)

JEFFERSON CITY, Mo. (DTN) -- Farmers in 10 states where the use of Enlist One and Enlist Duo herbicides had been restricted will have access to the products for the upcoming season.

The final biological opinion (BiOp) from the U.S. Fish and Wildlife Service (USFWS) determined that the registration of Enlist products is not likely to jeopardize the continued existence of endangered or threatened species or adversely modify their critical habitat.

The U.S. Environmental Protection Agency (EPA) announced Friday, Dec. 1, that it had posted the USFWS's final BiOp to the docket. The document outlines the removal of all countywide prohibitions for Enlist products in Arizona, Colorado, Louisiana, New York, Pennsylvania and South Carolina. It also establishes subcounty-level restrictions for counties in Alabama (1), Georgia (11), Tennessee (1) and Texas (16). In Florida, previous restrictions remain in place in 22 counties for both Enlist One and Enlist Duo, with restrictions on Enlist Duo only in two other counties.


In its BiOp, USFWS considered 22 threatened or endangered species -- from the Attwater's greater prairie chicken and dusky gopher frog to Virginia sneezeweed and the Panama City crayfish –- and analyzed if the registration of Enlist herbicides would jeopardize the continued existence of any of the species.

"While we expect that a number of individuals of some species will experience mortality or sublethal effects (i.e., reduction in growth), or indirect effects, which will result in reduced fitness, reproduction and dispersal for some individuals and populations, we do not expect these effects will appreciably reduce the likelihood of survival and recovery of these species in [the] wild," the USFWS wrote in its conclusion. "Thus, it is the Service's biological opinion that the registration of Enlist One and Enlist Duo, as proposed, is not likely to jeopardize the continued existence of endangered or threatened species."

In January 2022, the EPA initially granted seven-year registrations and labels for both Enlist Duo and Enlist One. Each contains the active ingredient 2,4-D choline and is intended for post-emergent application over genetically modified corn, cotton and soybeans.

The labels were among the first to include mitigation measures intended to protect federally threatened and endangered species. This "pick list" included off-field conservation buffers, such as vegetative filter strips, grassed waterways and field borders intended to reduce runoff and erosion. Also included were on-field conservation practices, such as reduced tillage in the form of no-till and strip-till, as well as planting cover crops.

These general mitigation measures remain in effect for all applications of Enlist One and Enlist Duo. In its analysis of the 22 species included in the final BiOp, USFWS concluded that only two -- the Attwater's greater prairie chicken and the Spring Creek bladderpod -- required species-specific mitigations to provide necessary protection. When considering the species' designated critical habitats, it was determined that a species-specific mitigation was necessary to protect the whorled sunflower critical habitat.


In a press release, Corteva Agriscience stated that the company anticipates expanded farmer access to Enlist herbicides for the 2024 growing season following the release of the USFWS's final BiOp.

"The issuance of the final BiOp supports the EPA's review and the removal of countywide restrictions, ultimately providing more farmers with certainty and access to effective, and more sustainable, weed-control options," said Robert King, Corteva executive vice president for crop protection, in the release, which reminded applicators that they should continue to abide by current product labels until supplemental labels are issued.

Soybean farmers who have rapidly adopted Enlist E3 soybeans as a means of combatting herbicide-resistant weeds also applauded news of the USFWS's final BiOp.

"The Fish and Wildlife Service's final Biological Opinion on Enlist confirms what we strongly suspected all along -- that Enlist can be used safely and in a manner that does not risk jeopardizing endangered species," said Alan Meadows, American Soybean Association director and soybean grower from Halls, Tennessee, in a statement to DTN. "The thoughtful, reasoned approach the agencies took to reach these conclusions should greatly reassure wildlife advocates, farmers, and in fact, all of us, that these important tools can be used safely and sustainably to support American agriculture. We look forward to working with EPA to incorporate these findings into the registrations for Enlist One and Enlist Duo in the months to come."

In an email to DTN, Brett Hartl, government affairs director at the Center for Biological Diversity, said that his organization was satisfied that USFWS "finally finished the BiOp and will help ensure that the EPA is doing what needs to be done to protect endangered species." He noted that the measures seem generally protective.

"The whole point of the BiOp is to ensure there is a monitoring and reporting regime that allows us to gauge the efficacy of the protections," Hartl wrote. "We think having an adaptable and responsive approach that allows for modest changes if they turn out to be needed will be best."

He added that when pesticide use limitation areas (PULAs) are created to protect a specific endangered species or its designated critical habitat, those areas should be targeted and below county level whenever possible "so that the areas that are vital to endangered species are fully protected, but areas that are not proximate to those lands are not encumbered.

"This is a work in progress," Hartl continued. "We should not expect the maps of PULAs to be perfect everywhere, but the more targeted, the better."


The issuance of the final biological opinion is the last step in EPA's formal consultation process with USFWS. In its announcement of the final BiOp for Enlist pesticide products, EPA stated that the agency will work with the registrant to implement the biological opinion. EPA intends to have label revisions approved in advance of the next growing season. Pesticide users should visit EPA's Bulletins Live! Two (BLT) website to determine if specific mitigation measures are required within the geographic area where they intend to apply Enlist herbicides.

The final biological opinion on Enlist Duo and Enlist One can be found here: https://www.regulations.gov/…

Access EPA's BLT website here: https://www.epa.gov/…

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

Follow him on X, formerly known as Twitter, @JasonJenkinsDTN.

Jason Jenkins