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[GreenYes] Background on Clopyralid concerns for composting
The following are background emails on the Clopyralid concerns for 
composting, previously posted on the US Composting Council listserve and 
the JTRnet listserve.

Gary Liss
Our regulatory agency is asking the question below.  Please reply to the
list.  I'll compile and forward the responses.

Jim Gilbert
Environmental Services Unit
Empire State Development
400 Andrews Street, Suite 710
Rochester, NY  14604
(716) 325-1944
Fax (716) 325-6505
Web Site:

Has anyone had any problems/issues with the herbicide "Clopyralid" and its
effect on compost, particularly its propensity to have a negative impact on
certain plants exposed to compost which contains this herbicide?

Reports coming from some other states indicate that compost produced from 
materials which contain grass clippings from turf treated with Clopyralid 
can be harmful to certain plants.  I understand that DOW would like to 
register this herbicide for homeowner/residential use.  One of the warnings 
that DOW wants to use on the product label is that grass clippings should 
not be used as compost feedstock until after the fifth cutting.  Is it even 
reasonable to assume that a homeowner would read the label, let alone 
follow such a direction?  What is your reaction to this and to the 
potential widespread residential use of this herbicide?

William Colden
625 Broadway, 9th Floor
Albany, NY 12233-7253
Date: Tue, 2 Oct 2001 11:49:32 -0400 (EDT)
From: "Alan Watts" <>
To: Multiple recipients of list <>

The following text contains excerpts from a discussion of this topic on the
US Composting Council's listserve from May of this year:

In October 1999, a multiple year vegetable crop study was begun at The
Pennsylvania State University with the goal of documenting the influence
of compost applications on soils and crops. The compost utilized in this 
research was produced by the University and was derived from campus yard 
waste (except grass clippings), animal manure, and food scraps from the 
student dining halls.

Soon after transplanting, symptoms resembling phenoxy-acid herbicide (e.g. 
2,4-D) damage were observed. Plants exhibited obvious growth abnormalities 
such as leaf cupping and strapping. This was most severe in the growing 
shoots and persisted for several weeks, becoming less conspicuous with 
plant age. A series of laboratory tests that confirmed that the compost 
utilized in the Penn State research had been contaminated. The culprit in 
this instance was clopyralid, and was detected at concentrations much 
higher than the minimum activity threshold of 1-2 parts per billion (ppb). 
The range in concentration between different batches has been from 17 to 
74.5 ppb.

Since the discovery of herbicide contamination at Penn State, it was 
determined that two products, Millenium and Confront (DowAgro), are being 
used on campus for broad-leaf weed control. Both of these herbicide 
formulations contain clopyralid as an active ingredient.
Clopyralid is found in several products used for broad-leaf control in 
turf-grass maintenance and row crop production. Collected plant residues--
-grass clippings, grain stubble---are mostly likely to be the primary 
source of contamination with this compound. This herbicide is capable of 
killing broadleaf plants in concentrations as low as 8 parts per billion 
and, unlike other herbicides, is not degraded in the composting process. 
The label on the herbicide states that the product is not to be used in 
situations where the grass clippings may be sent to municipal composting 
operations. It is applied in levels as high as 500 parts per million, 
meaning that a few improper applications can cause ordinary compost to be 
Picloram is an active ingredient found in products currently labeled for 
use in hay crops, including the Dow Agro products Grazon and Tordon. The 
harvested forage, when ingested by livestock, introduces the herbicide 
compound into the digestive tract of the animal where it is quickly passed 
via excrement. Any manure or manure saturated bedding that is used in the
manufacture of the compost then appears to serve as a source of contamination.

Both of these chemicals have been found in finished compost in eastern
Washington, and they definitely harm some plants. Tomatoes, peas and
beans are very susceptible to very small amounts of these chemicals.
WSU (Pullman,WA) paid a number of claims due to gardens being impacted with 
compost containing picloram residues. Compost sold by the Spokane Regional 
Compost Facility was determined to contain clopyralid after a nursery 
purchased it and lost their tomato plants. There are several other 
facilities around the country that have had this chemical in their compost 

Jim~ McNelly
The Compost Man

Jessie A. Lang
Recycling Coordinator, Spokane Regional Solid Waste System
Date: Tue, 2 Oct 2001 11:49:04 -0400 (EDT)
To: Multiple recipients of list <>
EPA's "Jobs Through Recycling" Grants Network

I recently attended a Professional Recyclers of Pennsylvania (PROP ) 
meeting and the contamination of compost with picloram and clopyralid was 
discussed in the composting session. Contact Cary Oshins or Patty Olenick 
for details.

Cary Oshins
County of Lehigh, PA
17 South Seventh Street
Allentown, PA 18101-2400
PHONE: 610-782-3046
FAX: 610-820-8257

PADEP Contact:
Patti Olenick, Compost Coordinator
Division of Waste Minimization
PA Dept. of Environmental Protection, 14th Floor
400 Market Street
Harrisburg, PA 17105
PHONE: 717-787-7382
FAX: 717-787-1904

Also check out these web links for information

Mike Giuranna
EPA, Region III
1650 Arch Street (3WC21)
Philadelphia, PA 19103-2029
215-814-3163 fax

Gary Liss
Gary Liss & Associates
4395 Gold Trail Way
Loomis, CA  95650-8929
Phone: 916-652-7850
Fax: 	  916-652-0485

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