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Russian Knapweed

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Russian knapweed
Russian knapweed, plants - Photo by Norman E. Rees; USDA, Agricultural Research Service
Scientific Name: 
Rhaponticum repens (L.) Hidalgo (ITIS)
Centaurea repens (L.), Acroptilon repens (L.) DC. (ITIS)
Common Name: 
Russian knapweed, Turkestan thistle, creeping knapweed, mountain bluet, Russian cornflower, hardheads
Native To: 
Eurasia (Zouhar 2001)
Date of U.S. Introduction: 
Early 1900s (Zouhar 2001)
Means of Introduction: 
Accidentally as a seed contaminant (Zouhar 2001)
Crowds out native species and desirable forage; toxic to horses (Zouhar 2001)

Distribution / Maps / Survey Status

University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.
USDA. APHIS. Cooperative Agricultural Pest Survey. National Agricultural Pest Information System.


University of Georgia. Center for Invasive Species and Ecosystem Health.


Google. YouTube; Montana Department of Agriculture.

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 Russian Knapweed.

Council or Task Force

Alberta Invasive Species Council (Canada).

See also: Fact Sheets for more information about individual invasive species, including those listed as "Prohibited Noxious" and "Noxious" under the Alberta Weed Control Act

Saskatchewan Invasive Species Council (Canada).
University of Alaska - Anchorage. Alaska Center for Conservation Science.
See also: Non-Native Plant Species List for additional factsheets (species biographies) and species risk assessment reports of non-native species present in Alaska and also non-native species currently not recorded in Alaska (potential invasives)

USDA. APHIS. PPQ. Center for Plant Health Science and Technology; California Department of Food and Agriculture.

University of Georgia. Center for Invasive Species and Ecosystem Health.

Centre for Invasive Species Solutions; Atlas of Living Australia; Australian Government. Department of Agriculture, Water and the Environment.

Federal Government
USDA. FS. Rocky Mountain Research Station. Fire Sciences Laboratory.
USDA. NRCS. National Plant Data Center.

USDA. ARS. National Genetic Resources Program. GRIN-Global.

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.

North Dakota State University. Extension Service.
Colorado State University Extension.
University of California. Statewide Integrated Pest Management Program.
New Mexico State University.
Colorado Weed Management Association.
Montana Weed Control Association.


  • Integrated Taxonomic Information System. Rhaponticum repens. [Accessed Sep 10, 2014].
  • Zouhar, K.L. 2001. Acroptilon repens. In: Fire Effects Information System. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.