Two-season decision adds tighter dicamba application limits, conservation requirements and drift safeguards as EPA reviews long-term path.
The U.S. Environmental Protection Agency (EPA) has announced new restrictions governing over-the-top dicamba herbicide applications in dicamba-tolerant cotton and soybean systems for the next two growing seasons, establishing what the agency describes as its most stringent set of mitigation measures for the herbicide to date.
The decision allows continued use of dicamba in these cropping systems while imposing tighter controls intended to address dicamba drift, volatility and ecological concerns. The time-limited registration will cover the 2026 and 2027 growing seasons and will be subject to further review based on performance data, incident reports and environmental monitoring.
Two-Season Registration with Expanded Safeguards
EPA says the updated pesticide registration is designed to balance grower access to weed management tools with protections for human health, neighboring crops and natural ecosystems.
The agency conducted a new evaluation using available data, peer-reviewed research and field results to complete human health and ecological risk assessments. According to EPA, dicamba drift and volatility remain documented concerns, particularly for sensitive plants and surrounding environments if mitigation measures are not followed.
Under the new label, EPA determined that over-the-top dicamba herbicide use does not present unreasonable risk to human health or the environment when applied according to required restrictions.
Did EPA Reduce Application Limits?
Among the most significant changes, the maximum allowable annual application rate has been reduced. Growers may now make no more than two applications of 0.5 pounds of dicamba per acre per year, for a total maximum of 1.0 pound per acre across all dicamba products.
The previous registration allowed up to four applications of 0.5 pounds per acre annually, with two permitted as over-the-top applications.
EPA says the reduction is intended to lower total environmental exposure and potential risk to sensitive species.
Does This Decision Strengthen Volatility and Drift Mitigation?
The updated registration requires increased use of volatility reduction agents. A minimum of 40 ounces per acre of an approved volatility reduction agent must be included with every application to limit the likelihood of dicamba volatilizing and moving off target after spraying.
Drift mitigation requirements remain in place, including mandatory drift reduction agents, coarse droplet size requirements, wind speed limits between 3 and 10 miles per hour and a 240-foot downwind buffer during application unless additional label-approved mitigations are used. Aerial applications remain prohibited.
Temperature and Timing Restrictions Added
EPA added temperature-based restrictions designed to address volatility risk. If forecast temperatures are between 85 and 95 degrees Fahrenheit on the day of or day after application, growers may treat no more than half of their untreated dicamba-tolerant acres in a county at one time. Remaining acres must wait at least two days before treatment.
Applications are prohibited when temperatures are forecast at or above 95 degrees Fahrenheit.
Timing limits also prohibit applications during temperature inversions, within 48 hours of forecast rainfall, when soils are saturated or outside specific daylight windows when inversion risk is higher.
For the first time, growers must implement runoff and erosion mitigation practices as part of dicamba use. Fields must achieve a minimum of three mitigation points using EPA-approved conservation practices, such as vegetative buffers, contour farming or cover crops. In certain pesticide use limitation areas where endangered species protections are heightened, six mitigation points are required.
EPA says these measures are intended to reduce movement of dicamba in runoff and eroded soil and to protect waterways and habitats.
Existing Requirements Remain in Place
The herbicide remains classified as a restricted use pesticide, meaning only certified applicators may use it. Annual applicator training, personal protective equipment requirements, a 24-hour restricted entry interval and record-keeping requirements continue under the updated registration.
Tank mixing with ammonium sulfate-containing products remains prohibited due to increased volatility risk.
What’s Next for Enforcement and Review?
EPA emphasized that label requirements are enforceable under the Federal Insecticide, Fungicide and Rodenticide Act, with penalties for noncompliance that may include civil fines or criminal enforcement for knowing violations.
The agency says it will work with states to monitor compliance and evaluate real-world outcomes during the two-season registration period. Manufacturers may be required to submit additional data as part of the review.
Future decisions on dicamba use will depend on performance results, incident reporting and environmental monitoring collected during this timeframe.
Still, Ongoing Debate Continues
Dicamba has been widely used in cotton and soybean production, particularly in regions managing herbicide-resistant weeds such as Palmer amaranth. At the same time, the herbicide has been at the center of ongoing disputes involving crop injury, dicamba drift and regulatory oversight.
EPA says feedback from farmers, workers, environmental organizations and the public informed the updated registration and mitigation requirements. The decision is positioned as an interim step intended to maintain access to weed-control tools while strengthening safeguards and gathering additional data to inform future regulatory direction.
Seed Industry Response Begins to Emerge
Industry response to EPA’s two-season dicamba decision is starting to take shape as companies and grower groups assess what the updated restrictions will mean for the 2026 and 2027 seasons.
“We welcome the EPA’s scientific review and registration decision for low-volatility dicamba herbicides. Now more than ever, growers need weed control options. Growers tell us they value the flexibility that dicamba, and XtendFlex soybeans and cotton adds to their operations,” Brian Naber, Bayer Crop Science president of North America & Australia/New Zealand region, said in a statement on Bayer’s website. “This new registration will give growers another vital tool to control tough-to-control and herbicide-resistant weeds.”
The company also indicated the registration will support continued dicamba-based weed management programs in dicamba-tolerant soybean and cotton systems and said it plans applicator training and stewardship efforts tied to the rollout.
Other registrants had not issued public statements as of publication.
