Registration of Dicamba for Use on Dicamba-Tolerant Crops
In 2018, EPA extended the registration for two years for over-the-top use (i.e. use on growing plants) of dicamba to control weeds in fields for cotton and soybean plants genetically engineered to resist dicamba. This decision was informed by extensive collaboration between EPA, the pesticide manufacturers, farmers, state regulators, and other stakeholders. The registration includes label updates that add protective measures to further minimize the potential for off-site damage. The registration will automatically expire on December 20, 2020, unless EPA further extends the registration.
View the documents supporting this decision:
Learn more about dicamba for use on dicamba-tolerant crops:
- What is dicamba?
- What additional steps is EPA taking to further minimize damage to non-target crops resulting from dicamba used on dicamba-tolerant crops (over-the-top applications)?
- What are EPA’s next steps?
- Are dicamba residues on food safe?
- How will the use of dicamba on dicamba-tolerant cotton and soybean affect pollinators, including bees?
- In what states is dicamba registered for use on dicamba-tolerant cotton and soybean?
1. What is dicamba?
Dicamba, a benzoic acid, is a widely used herbicide on agricultural crops, fallow land, pastures, turfgrass, and rangeland. It was first registered in the U.S. in 1967. Historically, most dicamba applications occurred in late winter or early spring for removal of broadleaf weeds prior to planting crops. It is registered for use in agriculture on corn, wheat, cotton, soybeans, and other crops.
In 2016, EPA first registered dicamba formulations for “over-the-top” use on growing dicamba-tolerant cotton and soybean plants during the 2017 growing season. In 2017 after a high number of alleged non-target incidents where sensitive plants were injured, EPA reached an agreement with manufacturers on measures to further minimize the potential for damage to neighboring crops from the use of over-the-top dicamba formulations used to control weeds in dicamba-tolerant cotton and soybeans. The registrants agreed to registration and labeling changes including making these products restricted-use, record keeping requirements, and certain additional spray drift mitigation measures for the 2018 growing season.
Only dicamba products registered for use on dicamba-tolerant cotton and soybean can be applied over-the-top. It is a violation of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) to use any dicamba product on crops that is not registered for over-the-top use on genetically engineered crops.
Dicamba is also registered for non-agricultural uses in residential areas and other sites, such as golf courses. At these types of sites, it is primarily used to control broadleaf weeds such as dandelions, chickweed, clover and ground ivy.
2. What additional steps is EPA taking to further minimize damage to non-target crops resulting from dicamba used on dicamba-tolerant crops (over-the-top applications)?
EPA worked with pesticide manufacturers, farmers, state regulators, and other stakeholders to develop the following label changes for over-the-top use of dicamba on dicamba-tolerant cotton and soybeans through the 2020 growing season:
- Only certified applicators may apply dicamba over the top (those working under the supervision of a certified applicator may no longer make applications)
- Prohibit over-the-top application of dicamba on soybeans 45 days after planting and cotton 60 days after planting
- For cotton, limit the number of over-the-top applications from 4 to 2 (soybeans remain at 2 OTT applications)
- Applications will be allowed only from 1 hour after sunrise to 2 hours before sunset
- In counties where endangered species may exist, the downwind buffer will remain at 110 feet and there will be a new 57-foot buffer around the other sides of the field (the 110-foot downwind buffer applies to all applications, not just in counties where endangered species may exist)
- Clarify training period for 2019 and beyond, ensuring consistency across all three products
- Enhanced tank clean-out instructions for the entire system
- Enhanced label to improve applicator awareness on the impact of low pH’s on the potential volatility of dicamba
- Label clean up and consistency to improve compliance and enforceability
3. What are EPA’s next steps?
The registration for all dicamba products registered for over-the-top use on genetically engineered cotton and soybeans will automatically expire on December 20, 2020, unless EPA acts to extend it. EPA will continue to coordinate with states and other stakeholders on dicamba applications through the 2020 season.
4. Are dicamba residues on food safe?
Yes. EPA performed the analysis required by the Federal Food, Drug and Cosmetic Act (FFDCA) and determined that residues on food are “safe” – meaning that there is a reasonable certainty of no harm to all reasonably identifiable subpopulations, including infants and children, from dietary and all other non-occupational exposure to dicamba.
5. How will the use of dicamba on dicamba-tolerant cotton and soybean affect pollinators, including bees?
Conservative, screening-level risk assessments have determined that this use of dicamba on dicamba-tolerant cotton and soybean, when used according to label directions, does not exceed EPA's level of concern for pollinators, including bees. Therefore, we expect there will be no adverse impacts to bees or other pollinators.
Learn more about EPA efforts to protect bees and other pollinators from pesticides.
6. In what states is dicamba registered for use on dicamba-tolerant cotton and soybean?
The registration for over-the-top use of dicamba on dicamba-tolerant cotton and soybean allows for use in:
- Alabama;
- Arkansas;
- Arizona;
- Colorado;
- Delaware;
- Florida;
- Georgia;
- Illinois;
- Indiana;
- Iowa;
- Kansas;
- Kentucky;
- Louisiana;
- Maryland;
- Michigan;
- Minnesota;
- Mississippi;
- Missouri;
- Nebraska;
- New Mexico;
- New Jersey,
- New York;
- North Carolina;
- North Dakota;
- Ohio;
- Oklahoma;
- Pennsylvania;
- South Carolina;
- South Dakota;
- Tennessee;
- Texas;
- Virginia;
- West Virginia; and
- Wisconsin.