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Scotch Thistle

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Scotch thistle
Scientific Name:
Onopordum acanthium L. (ITIS)
Common Name:
Scotch thistle, cotton thistle, heraldic thistle, woolly thistle
Scotch thistle, flowers - Photo by Steve Dewey; Utah State University
Native To:
Date of U.S. Introduction:
Means of Introduction:
Crowds out desirable forage (Schuster and Prather 2003)

Distribution/Maps/Survey Status



Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Scotch Thistle.

Council or Task Force

Washington State Recreation and Conservation Office. Washington Invasive Species Council.


IUCN. Species Survival Commission. Invasive Species Specialist Group.
University of Georgia. Center for Invasive Species and Ecosystem Health.

Federal Government

USDA. NRCS. National Plant Data Center.
USDA. ARS. National Genetic Resources Program. GRIN-Global.

International Government

New South Wales Department of Primary Industries (Australia).
Victoria Department of Jobs, Precincts and Regions (Australia). Agriculture.
Australian Government. Department of the Environment and Energy.

State and Local Government

Washington State Noxious Weed Control Board.
California Department of Food and Agriculture.
See also: Included on California's noxious weed list; see Encycloweedia: Program Details for additional resources
Colorado Department of Agriculture. Conservation Services Division. Noxious Weed Program.


University of California. Weed Research and Information Center.
See also: Weeds in Natural Areas for more information sheets
University of Idaho; Oregon State University; Washington State University. Pacific Northwest Extension.


Colorado Weed Management Association.