Update on EPA Release of Clopyralid Interim Decision

Losing the battle but winning the war? The U.S. EPA released its clopyralid interim decision (ID), and it’s not all bad news!

The EPA released the ID on the reregistration of clopyralid on March 18, and, while we did not get much of what we asked for, taking a long view shows significant progress. Unlike earlier rounds of reregistration, the ID clearly states "clopyralid is persistent in compost and can cause non-target plant damage from use of composted material contaminated with clopyralid residues.” In response to our comment letter, it states, "EPA acknowledges that clopyralid and other persistent herbicides pose significant risks to the compost community, which have been reported in multiple incidents, some as recent as May and June 2020.”

To address the compost contamination concern, the ID includes several policies:

• focusing on turf and pasture as likely sources of compost contamination versus crop residues
• requiring label changes intended to prevent the movement of treated plant materials into compost via turf grass and pasture, including via hay grown for feed or bedding
• updating the required label pictogram for greater clarity (see sample)
• requiring animals fed clopyralid-treated food to be fed non-treated food for three days before being placed in a situation where the manure may be collected
• requiring 18 months pass before treated plant materials can move off-site for feed, bedding or composting
• creating and making available educational materials and stewardship plans
• considering compost contamination in the review of future herbicide evaluations

On the other hand, the EPA gave us very little of what we asked for, including:

• not limiting clopyralid to non-harvested crops
• not requiring notification of clopyralid use to follow the harvested crops
• not making clopyralid a limited use pesticide that can only be applied by licensed applicators
• not requiring training of applicators and state extension agents

One other positive note: The EPA has agreed, at least in principle, with the NRCS’s call for a multi-stakeholder working group to address not only clopyralid but other persistent herbicides as well. "The Agency looks forward to working with USCC to create best management practices for composting and to resolve remaining uncertainties with respect to persistent herbicides in compost.” The USCC will be part of that group, and we will report back to membership on those meetings.

If you are interested in reading the full ID, including the agency's response to ours and others' comments, go to www.regulations.gov/document/EPA-HQ-OPP-2014-0167-0622.