[gardeners] don't poison your compost/gardens

Margaret Lauterbach (gardeners@globalgarden.com)
Thu, 10 Jan 2002 09:46:26 -0700

Be on the alert for a chemical named Clopyralid, trade name Benazalox, in 
herbicides.  It's very persistent, and may retain its herbicidal qualities 
for a very long time (a half-life in soil of 15 to 287 days).  This 
chemical may not be available to home gardeners, but where you're likely to 
run into it is composting clippings from lawns treated by a lawn care 
company.  Brand names containing this chemical include Stinger, Reclaim, 
Transline, and according to the L.A. Times, Lontrel, Confront, Hornet, 
Scorpion, and Redeem.  Those are the Dow products. Products with Clopyralid 
from other manufacturers include Millenium, Momentum, Chaser Ultra, 
Battleship, Strike Three, and TruPower.

A friend said her lawn care bill identified the herbicide as TruPower, so 
she regards that compost pile as toxic. The Times article reports one lawn 
care company uses Confront, and the owner said residual herbicidal activity 
may continue for up to 18 months. Gardens in the West that have suffered 
from this residual effect range reportedly from Spokane to Los Angeles, and 
they've popped up in Pennsylvania and NZ.  There are undoubtedly unreported 
instances as well.  The chemical is an effective herbicide, with very low 
toxicity to humans. Unfortunately its long-lasting effects have appeared 
even in commercial composts.  Margaret L