An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »


E. I. du Pont de Nemours and Company Imprelis Order

(Washington, DC - August 11, 2011) The U.S. Environmental Protection Agency (EPA) today issued an order to E.I. DuPont de Nemours (DuPont) directing the company to immediately halt the sale, use or distribution of Imprelis, an herbicide marketed to control weeds, vines and certain grasses in recreational areas such as golf courses and commercial properties such as sod farms. The order follows EPA's investigation into why a large number of evergreens and other trees have been harmed following the use of the herbicide.

On this page:

EPA issued a Stop Sale, Use or Removal Order (SSURO) to the E.I. du Pont de Nemours and Company (DuPont) for potential violations of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and ordered DuPont to immediately cease the distribution, sale, use or removal of Imprelis Herbicide products under its ownership, control, or custody.


DuPont is the registrant of Imprelis Herbicide (EPA Registration No. 352-793) with the active ingredient aminocyclopyrachlor (CASRN 858956-35-1). Beginning in June 2011, EPA started receiving complaints from state pesticide agencies regarding evergreen damage related to the use of Imprelis. As of August 2011, DuPont has submitted to the Agency over 7,000 adverse incident reports involving damage (including death) to non-target trees - primarily Norway spruce and white pine - related to the application of Imprelis. Test data from DuPont has confirmed certain coniferous trees, including Norway spruce and balsam fir, as susceptible to being damaged or killed by the application of Imprelis. EPA continues to collect information from DuPont, state agency investigations, inspections and data analyses. The Agency continues to investigate possible causes of the evergreen damage.

Top of Page

Overview of Company and Pesticide Product

DuPont, along with its subsidiaries, is a global company offering a wide range of products and services in agriculture, nutrition, electronics, communications, safety and protection, home and construction, transportation and apparel. DuPont's Imprelis Herbicide was approved by the EPA in August 2010 for use as a post-emergent broadleaf weed control. It has been distributed and sold in 1 gallon, 2.5 gallon and 4.5 fl. oz. size containers. DuPont's Imprelis is registered for use in all but two states (California and New York), Washington, D.C., and Puerto Rico, and has been distributed and sold primarily to pest control professionals servicing the lawn, golf, turf and weed control sectors from New Jersey to Wisconsin. More information on Imprelis Herbicide (PDF) (11 pp, 647 K, About PDF).

Top of Page

Potential Violations

EPA has reason to believe Imprelis Herbicide is in violation of FIFRA based on DuPont's own test data and information gathered during EPA and state investigations. The approved end-use label for Imprelis does not include Norway spruce and white pine as target species. The directions for use and/or warning or caution statements on DuPont's Imprelis labeling are inadequate to protect non-target species, such as conifer trees, thus resulting in a pesticide product that is misbranded under sections 2(q)(1)(F) and/or (G) of FIFRA. Any distribution or sale of a misbranded product is in violation of FIFRA § 12(a)(1)(E).

Top of Page

Summary of the Order

Under the SSURO, Imprelis products under the ownership, control, or custody of DuPont may not be distributed or sold, moved, or removed for disposal from any facility or establishment, for any reason, other than in accordance with the EPA's written approval. More information on the use of SSUROs.

Top of Page

For more information, contact:

Tom Charlton
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., N.W.
Washington, DC 20460-0001
(202) 564-6960
Tom Charlton (

Top of Page