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National Invasive Species Information Center
U.S. Department of Agriculture
Home / Terrestrial Invasives / Terrestrial Plants / Russian Knapweed

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)
Synonym: 
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)
Impact: 
Crowds out native species and desirable forage; toxic to horses (Zouhar 2001)

Distribution / Maps / Survey Status

Early Detection & Distribution Mapping System (EDDMapS) - Russian Knapweed
University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.
Pest Tracker - Survey Status of Russian Knapweed
USDA. APHIS. Cooperative Agricultural Pest Survey. National Agricultural Pest Information System.

Images

Google Images - Russian Knapweed
Google.
Invasive.org - Russian Knapweed
University of Georgia. Center for Invasive Species and Ecosystem Health.

Videos

YouTube - Russian Knapweed

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
Fact Sheet: Russian Knapweed (Jan 2014) (PDF | 436 KB)
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
Russian Knapweed (PDF | 1.95 MB)
Saskatchewan Invasive Species Council (Canada).
Partnership
Alaska Exotic Plants Information Clearinghouse (AKEPIC): Species Biography - Species Biography - Russian Knapweed (Feb 4, 2011) (PDF | 262 KB)
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)
Federal Noxious Weed Disseminules of the U.S. - Fact Sheet: Acroptilon repens

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

Invasive Plant Atlas of the United States - Russian Knapweed
University of Georgia. Center for Invasive Species and Ecosystem Health.
Invasive Species Compendium - Rhaponticum repens
CAB International.
Texas Invasives Database - Acroptilon repens
TexasInvasives.org.
Weeds Australia - Rhaponticum repens

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

Federal Government
Field Guide for Managing Russian Knapweed in the Southwest (Feb 2015) (PDF | 2.04 MB)
USDA. FS. Southwestern Region.
See also: Weed Field Guides for more species
Fire Effects Information System (FEIS) - Acroptilon repens
USDA. FS. Rocky Mountain Research Station. Fire Sciences Laboratory.
PLANTS Database - Hardheads
USDA. NRCS. National Plant Data Center.
U.S. National Plant Germplasm System - Rhaponticum repens

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

State and Local Government
Class B Noxious Weed: Russian Knapweed
Washington State Noxious Weed Control Board.
Encycloweedia: Data Sheet - Russian Knapweed
California Department of Food and Agriculture.
See also: Included on California's noxious weed list; see Encycloweedia: Program Details for additional resources
Noxious Weed Species - Russian Knapweed

Colorado Department of Agriculture. Conservation Services Division. Noxious Weed Program.

Academic
MontGuide - Biology, Ecology and Management of Montana Knapweeds (Aug 2017)

Montana State University Extension.

Know Your Knapweeds
North Dakota State University. Extension Service.
Natural Resources Series: Range - Russian Knapweed
Colorado State University Extension.
Weed Gallery: Russian Knapweed
University of California. Statewide Integrated Pest Management Program.
Weed Information - Russian Knapweed
New Mexico State University.
Professional
Noxious Weed Information - Russian Knapweed
Colorado Weed Management Association.
Weed Identification - Russian Knapweed
Montana Weed Control Association.

Citations

  • 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.