This post was updated Aug. 12, 2011.
Since 2008, we’ve
been reporting on the dangers of pyralid herbicides (including Milestone,
Forefront and other trade names), which turn grass clippings, manure or hay
into killer compost or mulch that can ruin gardens and farmland for years.
Despite ample
evidence that these deadly herbicides are damaging fields and gardens — and
despite our calls for the companies and the Environmental Protection Agency
(EPA) to solve this problem — we learned another dangerous pyralid herbicide,
aminocyclopyrachlor, had been widely sold in the spring of 2011 following its
approval by the EPA in August 2010. Invented by scientists at DuPont and sold
as “Imprelis,” aminocyclopyrachlor was marketed to control weeds in cool-season
lawn grasses, especially bluegrass.
After one season of
use, Imprelis has been implicated in the injury or death of thousands of trees.
Conifers that are growing in or near grassy areas treated with
Imprelis, and are showing new growth that is brown and twisted, have
been reported in Pennsylvania, Minnesota, Iowa, Delaware , Indiana, Nebraska , Wisconsin, and several other states. Michigan State has published an advisory on What to Do With Imprelis-Affected Trees, and Purdue University in Indiana has set up channels for Imprelis related herbicide complaints, as have Nebraska and Wisconsin. And what will happen when the chipped wood from these poisoned trees ends up at
compost facilities? DuPont never denied Imprelis-treated lawns would create
killer compost. Lost in a 19-item bulleted list on Page 7 of the nine-page
Imprelis label, we found this language:
“Do not use grass
clippings from treated areas for mulching or compost, or allow for collection
to composting facilities. Grass clippings must either be left on the treated
area, or, if allowed by local yard waste regulations, disposed of in the trash.
Applicators must give verbal or written notice to property owner/property
managers/residents to not use grass clippings from treated turf for mulch or
compost.”
Come on, people! How
likely is it that most users will remember this from a 9-page label, let alone
warn others not to use clippings for hay, mulch or compost? Despite our
knowledge of the severe problems these herbicides are causing, the EPA
continues to allow chemical companies to sell them and hide behind their “the
label is the law” excuse by putting unrealistic instructions and a liability
release on the product labels.
Somehow, DuPont’s
“over 400 field trial protocols” failed to detect that Imprelis would kill
trees. As damage reports began to surface in late spring, DuPont’s response was
to send a letter to turf management professionals asking for help as they
“continue their work.” The letter said “to be careful that no spray treatment,
drift or runoff occurs that could make contact with trees, shrubs or other
desirable plants, and stay well away from exposed roots and the root zone of
trees and shrubs” when applying Imprelis. It also said to “consult a certified
arborist if you are uncertain about the root zone of specific tree species.”
Tree roots often spread three times as wide as the branches, so following these
guidelines, few properties could be safely treated with Imprelis.
On July 5, 2011,
DuPont issued recommendations for handling trees affected by
aminocyclopyrachlor. The company’s justification for selling this deeply flawed
product was that it had been approved by the EPA. We think the government
shouldn’t have to force chemical companies to do the right thing, but
regardless, the EPA must stop allowing herbicides to be registered with such
unrealistic guidelines for legal uses.
On Aug. 5, DuPont
finally halted sales of Imprelis after the EPA threatened to force it to do so. University extension services in 22 states have received
reports of damage consistent with that caused by Imprelis, and a team of
specialists at Purdue University has stated
this chemical should not be used until we know more about its effects. Numerous lawsuits have been filed alleging damage
from what DuPont labeled “the most scientifically advanced turf herbicide in
over 40 years.”
The world is running
out of oil, and that means we are running out of chemical fertilizer. We must
expand our systems to capture and recycle organic materials if we are to
maintain the fertility of our soils.
You can express your
concern about persistent herbicides to Dan Kenny, EPA herbicide branch chief:
703-305-7546; kenny.dan@epa.gov. To contact DuPont directly, call its Imprelis
hotline at 866-796-4783 or email Mike Kuflik, DuPont sales manager for U.S. turf and
ornamentals: michael.d.kuflik@usa.dupont.com.
Photo: Purdue University Extension
Related Reading:
Oct 2008: Watch Out For Killer Compost
July 2009: Milestone Herbicide Creates Killer Compost
September 2009: Contaminated Compost — Coming Soon to a Store Near You
