06 Feb EPA Issues Two-Season Registration With New Restrictions for Over-the-Top Dicamba Use
The U.S. Environmental Protection Agency (EPA) has announced a time-limited registration allowing over-the-top (OTT) applications of dicamba on dicamba-tolerant cotton and soybean crops for the next two growing seasons. The decision includes a series of new and existing application requirements intended to address drift, volatility and environmental concerns associated with dicamba use.
Dicamba products have been available for sale and use in U.S. agriculture; this action specifically addresses conditions and restrictions for OTT applications. EPA stated the decision followed a pesticide registration review process that included analysis of human health and ecological risks using available data, independent studies, public comments and field information.
EPA indicated that off-target movement of dicamba, including drift and volatility, presents potential risks to sensitive plants, neighboring farms and natural ecosystems. The agency stated that updated label requirements and mitigation measures were developed to address these risks. According to EPA, applications made in accordance with the new label directions are not expected to pose unreasonable risks to human health or the environment.
The approval is limited to two growing seasons and will be subject to further evaluation based on performance data, incident reports and environmental monitoring information collected during the approval period.
NEW RESTRICTIONS FOR THE 2026 REGISTRATION
- Maximum application rate reduced: A maximum of two applications of 0.5 lbs. of dicamba per acre may be made annually, for a maximum of 1.0 lb. of all dicamba products annually. (The 2020 registration permitted up to four applications of 0.5 lbs./acre — only two of which could be OTT — for a total of 2.0 lbs. annually.)
- Volatility Reduction Agent requirement increased: A total of 40 oz./acre of an approved Volatility Reduction Agent (VRA) must be included with every application.
- Mandatory conservation practices: Applicators must implement runoff and erosion mitigation practices. Growers must obtain three mitigation points from EPA’s certified conservation practices menu on each treated field. In designated pesticide use limitation areas (PULAs), six mitigation points are required.
- Temperature-based application limits:
- When forecast temperatures are between 85°F and 95°F on the day of or the day after application, only up to 50% of untreated dicamba-tolerant cotton and soybean acres in a county may be treated at that time.
- Remaining acres may not be treated until at least two days after the initial application.
- Applications are prohibited when temperatures are forecast to reach or exceed 95°F on the day of or the day after application.
LEGACY RESTRICTIONS RETAINED IN THE 2026 REGISTRATION
- Restricted Use Pesticide designation: Products remain classified as Restricted Use Pesticides and may only be applied by certified applicators.
- Annual mandatory training: Certified applicators must complete annual dicamba-specific training addressing label requirements, best management practices and environmental protections.
- Personal protective equipment (PPE): Label-approved PPE is required for loaders, mixers, handlers and applicators.
- 24-hour Restricted Entry Interval (REI): Entry into treated fields is prohibited for 24 hours following application.
- Mandatory Drift Reduction Agent (DRA): An approved DRA must be included in all tank mixes.
- Downwind spray drift buffers: A 240-foot downwind spray drift buffer must be maintained during application. The buffer distance may be reduced only when additional label-approved mitigation measures are implemented.
- Strict application timing restrictions: Applications are prohibited during temperature inversions; within 48 hours ahead of forecast rainfall; when soils are saturated; and within one hour after sunrise or after two hours before sunset.
- Proximity restrictions: Applications may not occur when dicamba-sensitive crops or plants are located downwind.
- Wind speed requirements: Applications must occur only when wind speeds are between 3 and 10 miles per hour.
- Droplet size requirements: Applications must use coarse or coarser spray droplets.
- Spray release height: Spray nozzles must be positioned no higher than two feet above the ground or crop canopy.
- Aerial application prohibition: Aerial application methods remain prohibited.
- Tank mixing restrictions: Tank mixing with ammonium sulfate-containing products is prohibited.
- Recordkeeping requirements: Applicators must maintain detailed records documenting each application in accordance with label requirements.
COMPLIANCE AND ENFORCEMENT
EPA stated that all label directions are legally enforceable under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). Failure to comply with label requirements may result in civil penalties or, in cases of knowing violations, potential criminal enforcement. EPA indicated it will coordinate with state regulatory agencies to monitor compliance.
ONGOING REVIEW
EPA reported receiving comments from agricultural stakeholders, workers, environmental organizations and members of the public during the review process. The agency stated that it will conduct a comprehensive evaluation of data collected during the two-season approval period before considering any future regulatory actions related to OTT dicamba uses.