Last week NAAA submitted comments to the EPA as part of the re-registration review process of pesticide active ingredients. The EPA is required by FIFRA to review the registrations for all crop protection products every 15 years. The active ingredients commented on were a group of ALS inhibiting herbicides and Trifluralin. The nine ALS inhibiting herbicides included Bispyribac-sodium, Diclosulam, Florasulam, Flucarbazone-sodium, Imazamox, Imazapic, Imazaquin, Imazethapyr, and Penoxsulam. All the comments submitted were on proposed interim decisions. Interim decisions are being used by the EPA instead of a full reregistration of a product because Endangered Species Act and pollinator protection assessments still need to be completed for most products.

NAAA largely agreed with the proposed requirements for aerial application in the interim decisions. The drift mitigation language showed EPA has been listening to previous comments from NAAA. Prior proposed interim decisions for products reviewed earlier had capped wind speeds for aerial applications at 10 mph. The proposed drift mitigations strategies for the ALS inhibiting herbicides and Trifluralin increased the limit on wind speed to 15 mph. The only additional requirement for applying in wind speeds of 11 to 15 mph is that boom length be reduced to a maximum 65 percent of wingspan for fixed wing aircraft and a maximum of 75 percent of rotor diameter for helicopters. For applications at wind speeds at 10 mph or lower, maximum boom length would be 75 percent of wingspan for fixed wing aircraft or 90 percent of rotor diameter for helicopters.

Additional drift mitigation language included not making applications during an inversion and a half swath displacement would be required on the downwind edge of fields. Maximum aircraft height would be limited to 10 feet unless safety required a greater height. For the ALS inhibiting herbicides, a medium droplet size (based on the American Society of Agricultural and Biological Engineers (ASABE) Standard S572.1 for droplet size classification) was proposed for post emergence applications and a coarse droplet size for preemergence applications. The proposed droplet size for Trifluralin was coarse.