EPA Announces Proposed Registration of Pesticide Trifludimoxazin

Released June 11, 2025

Today, the U.S. Environmental Protection Agency (EPA) released for public comment its proposed registration for one technical and five end-use products containing the new active ingredient trifludimoxazin, a broad-spectrum herbicide used for control of broad leaf and grass weed species. Among five end-use products, three are formulated with trifludimoxazin as the only active ingredient while the other two are co-formulated products with saflufenacil, an already approved active ingredient. This new active ingredient would give farmers an additional tool to help manage crops and increase yields in order to provide a healthy and affordable food supply for our country.

The trifludimoxazin registrations are supported by human health and ecological risk assessments as well as a biological evaluation for the pesticide under the Endangered Species Act (ESA). No human health risks of concern were identified when trifludimoxazin is used according to the label. EPA did not identify any potential risks of concern for freshwater or estuarine/marine invertebrates, fish, aquatic-phase amphibians, mammals, or birds (surrogates for terrestrial-phase amphibians and reptiles) on an acute or chronic exposure basis, or acute direct risks to bees, when trifludimoxazin is used according to the label. EPA did identify potential risks for terrestrial, wetland, and aquatic plants, as well as potential chronic risks to bees and non-Apis terrestrial invertebrates that may forage on fields that have been treated with trifludimoxazin products containing the co-formulant saflufenacil. 

The following mitigation measures found on the products’ labeling address on- and off-field effects to non-target species, including listed species: 

• Instructing users to access and follow any applicable endangered species bulletin from “Bulletins Live! Two” web-based system for all additional directions and restrictions. 
• Approving use only in the contiguous United States. 
• Not approving use for any non-agricultural use sites.
• Designating 110 ft and 15 ft spray drift buffers to sensitive areas, for aerial and ground applications respectively.
• Instructing users to access the EPA’s Mitigation Menu website and choose among the mitigation and/or mitigation relief measures to meet or exceed 6-point runoff mitigations required for trifludimoxazin before applying the product.

With these mitigations in place, EPA’s draft biological evaluation predicts that the use of trifludimoxazin will not result in a likelihood of future jeopardy of any listed species, or a likelihood of adverse modification for any designated critical habitat. 

Next Steps

After considering public comments on the proposed registration decision, the draft risk assessments and the draft effects determinations, EPA will decide whether the registration action meets the standard for registration under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). If EPA determines that the registration action can be granted, EPA will finalize the biological evaluation. If a final biological evaluation finds that trifludimoxazin may affect any listed species or critical habitats, then EPA will initiate ESA consultation and share its findings with the U.S. Fish and Wildlife Service or the National Marine Fisheries Service (collectively referred to as the Services), as appropriate.

During formal consultation, the Services use the information in EPA’s final biological evaluation to inform their biological opinions. While EPA has made predictions about the likelihood of jeopardy and adverse modification as part of its biological evaluation, the Services are responsible for making the final jeopardy/adverse modification findings and have the sole authority to do so. If the Services determine in their final biological opinions that additional mitigations are necessary to address any jeopardy or adverse modification determination or to address any incidental take, then EPA will work with the registrant to ensure that any necessary registration or labeling changes are made.

To read more about the proposed registration of trifludimoxazin and to comment, see docket ID EPA-HQ-OPP-2022-0649 at www.regulations.gov. The public comment period will be open for 30 days, closing on July 11, 2025.