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

Spotted Knapweed

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Spotted knapweed
Spotted knapweed, flowers - USDA APHIS PPQ, Oxford, North Carolina
Scientific Name: 
Centaurea stoebe L. subsp. micranthos (Gugler) Hayek (ITIS)
Synonym: 
Centaurea biebersteinii DC., Centaurea maculosa auct. non Lam. (ITIS)
Common Name: 
Spotted knapweed
Native To: 
Europe (Zouhar 2001)
Date of U.S. Introduction: 
Late 1800s (Zouhar 2001)
Means of Introduction: 
Accidentally through contaminated seed or ballast (Zouhar 2001)
Impact: 
Crowds out native species and forage for livestock (Zouhar 2001)

Distribution / Maps / Survey Status

Early Detection & Distribution Mapping System (EDDMapS) - Spotted Knapweed
University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.

Images

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

Videos

YouTube - Spotted Knapweed
Google. YouTube; DOI. National Park Service. Great Lakes Restoration Initiative.
YouTube - Spotted 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 Spotted Knapweed.

Council or Task Force
Factsheet - Knapweeds (Mar 2019) (PDF | 1.83 MB)

Invasive Species Council of British Columbia (Canada).

See also: Publications for more resources

Fact Sheet: Spotted Knapweed (Jan 2014) (PDF | 801 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

Priority Species: Knapweeds

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

Partnership
Alaska Exotic Plants Information Clearinghouse (AKEPIC): Species Biography - Spotted Knapweed (Feb 7, 2011) (PDF | 148 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)
Global Invasive Species Database - Centaurea biebersteinii (herb)
IUCN. Species Survival Commission. Invasive Species Specialist Group.
Invasive Plant Atlas of the United States - Spotted Knapweed
University of Georgia. Center for Invasive Species and Ecosystem Health.
Invasive Species Compendium - Centaurea stoebe subsp. micranthos
CAB International.
Weeds Australia - Spotted Knapweed (Centaurea stoebe subsp. australis)

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

Federal Government
Biology and Biological Control of Knapweeds, FHTET-2011-05 (2012) (PDF | 45.5 MB)

USDA. FS. Forest Health Technology Enterprise Team.

See also: Invasive Species Publications for more publications
Fire Effects Information System (FEIS) - Centaurea maculosa
USDA. FS. Rocky Mountain Research Station. Fire Sciences Laboratory.
PLANTS Database - Spotted Knapweed
USDA. NRCS. National Plant Data Center.
U.S. National Plant Germplasm System - Centaurea stoebe

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

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

Missouri Department of Conservation.

See also: Invasive and Problem Plant Control (scroll to Invasive Plants section) for more information to help you identify and control most common invasive plants in Missouri

Invasive Plants in Pennsylvania: Black, Brown and Spotted Knapweed (PDF | 1.2 MB)

Pennsylvania Department of Conservation and Natural Resources.

See also: Invasive Plant Fact Sheets for plant species (trees, shrubs, vines, herbs and aquatic plants) that have impacted the state's natural lands

King County (Washington) Noxious Weed Control Program - Spotted Knapweed

King County Department of Natural Resources (Washington). Water and Land Resources Division.

Noxious Weed Species ID- Spotted & Hybrid Knapweed

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

Spotted Knapweed

Wisconsin Department of Natural Resources.

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

Montana State University Extension.

Invasive Plant Fact Sheet - Spotted Knapweed (Nov 2011) (PDF | 167 KB)
University of Pennsylvania. The Pennsylvania Flora Project of Morris Arboretum.
See also: Invasive Plant Fact Sheets for additional invasive plants in Pennsylvania
Introduced Species Summary Project - Spotted Knapweed
Columbia University. Center for Environmental Research and Conservation.
Know Your Knapweeds
North Dakota State University. Extension Service.
Natural Resources Series: Range - Diffuse and Spotted Knapweed
Colorado State University Extension.
Noxious Weeds of Nebraska - Spotted and Diffuse Knapweed
University of Nebraska - Lincoln. Cooperative Extension.
Ohio Perennial & Biennial Weed Guide - Spotted Knapweed

Ohio State University. Ohio Agricultural Research and Development Center.

Professional
Noxious Weed Information - Spotted Knapweed
Colorado Weed Management Association.
Weed Identification - Spotted Knapweed
Montana Weed Control Association.

Citations

  • Integrated Taxonomic Information System. Centaurea stoebe ssp. micranthos. [Accessed Mar 22, 2015].
  • Zouhar, K. 2001. Centaurea maculosa. In: Fire Effects Information System. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.