NAAA Attempts to Reverse EPA Decision Banning Certain Types of Aerial Applications on New Herbicide Formulation

NAAA submitted comments to the EPA at the end of last week on a proposed registration for a new herbicide, glufosinate-P. While EPA is treating glufosinate-P as a new herbicide, it is in fact a new formulation of an existing herbicide, glufosinate. It is intended for use on both conventional and glufosinate resistant crops.

The proposed registration memorandum and label from EPA allowed for aerial applications of glufosinate-P on glufosinate resistant crops but banned aerial from all other applications including burndown and non-crop uses. The EPA’s concern was due to potential risk to endangered species. NAAA strenuously objected, pointing out that EPA used the inaccurate and antiquated Tier 1 AgDRIFT model for its risk assessments. EPA has recently announced they will be taking NAAA’s recommendations to modernize their aerial drift modeling process in order to improve the accuracy of their drift estimates, so NAAA suggested EPA redo the risk assessments for glufosinate-P using the new process.

NAAA also recommended EPA require burndown and non-crop aerial applications be made with a larger droplet size and a shorter boom length to further mitigate drift. When combined with the wind-directional buffer zones EPA did propose, NAAA pointed out that due to the drift potential that was considerable reduced using the updated model and new, safer aerial application set up practices there was no reason to ban any type of aerial applications of glufosinate-P.

NAAA also took exception to several label statements for the glufosinate-P product, including requirements for nozzle selection and setup that are based on outdated science. The label also requires a minimum GPA for aerial applications that actually reduces efficacy and increases the risk of drift. Click here to read NAAA’s comments.