Spotted Knapweed

Scientific name: Centaurea stoebe L. subsp. micranthos (Gugler) Hayek

Synonyms: Centaurea biebersteinii auct., Centaurea maculosa auct. Amer., Centaurea maculosa subsp. micranthos Gugler (basionym)

Common name: Spotted knapweed

Native To: Europe

Date of U.S. Introduction: Late 1800s

Images: Invasive.org and Google

Means of Introduction: Accidentally through contaminated seed or ballast

Impact: Crowds out native species and forage for livestock

Current U.S. Distribution:

• National Agricultural Pest Information System - Pest Tracker - Reported Status
• PLANTS Database map (see complete PLANTS Profile for county distribution and native status)
• Early Detection & Distribution Mapping System (county distribution for Southeastern States)

States Where Reported Invasive: WeedUS Database map

Management Plans: Plants / Knapweeds

Selected Internet Resources:

• Federal Government
• State Government
• University/Academic
• International
• Organizations

Centaurea biebersteinii
Integrated Taxonomic Information System.
Taxonomy

Spotted Knapweed - Plant Invaders of Mid-Atlantic Natural Areas (2002)
DOI. National Park Service and Fish and Wildlife Service.
Identification/Description; Photographs; Controls

Centaurea biebersteinii DC. (Spotted Knapweed) - Noxious and Nuisance Plant Management Information System (PMIS)
United States Army Corps of Engineers. Engineer Research and Development Center. Environmental Laboratory.
Identification/Description; Photographs; Introduction History; Impacts; Distribution

Centaurea stoebe Article Citation Search - AGRICOLA Database
USDA. National Agricultural Library.
Research; Special Note: NAL Catalog Search (resources)

Centaurea stoebe L. subsp. stoebe- Germplasm Resources Information Network (GRIN)
USDA. ARS. National Genetic Resources Program.
Taxonomy

Spotted Knotweed - Biological Control of Invasive Plants in the Eastern United States, FHTET-2002-04
USDA. Forest Service.
Taxonomy; Identification/Description; Photographs; Distribution; Introduction History; Impacts; Life Cycle; Habitat; Controls

Biology and Biological Control of Knapweed, FHTET-2001-07, 2nd Edition
USDA. Forest Service.
Taxonomy; Identification/Description; Photographs; Distribution; Introduction History; Impacts; Life Cycle; Habitat; Controls

Centaurea maculosa - Fire Effects Information System (FEIS)
USDA. Forest Service. Rocky Mountain Research Station. Fire Sciences Laboratory.
Taxonomy; Identification/Description; Introduction History; Impacts; Life Cycle; Habitat; Distribution; Controls; Special Note: References

Spotted Knapweed - Weed of the Week (Mar 15, 2006; PDF | 194 KB)
USDA. FS. Northeastern Area. Forest Health Protection.
Identification/Description; Photographs; Introduction History; Impacts; Habitat; Distribution; Controls

Spotted Knapweed - Noxious Weed
USDA. Sawtooth National Forest.
Identification/Description; Photographs; Controls

Plant Profile for Centaurea biebersteinii - PLANTS Database
USDA. NRCS. National Plant Data Center.
Taxonomy; Photographs; Illustrations; Distribution; Legal Aspects

Centaurea maculosa - An Assessment of Exotic Plant Species of Rocky Mountain National Park
DOI. Northern Prairie Wildlife Research Center.
Impacts; Habitat; Distribution; Controls; Special Note: References

Spotted Knapweed
Arizona Department of Transportation. Intermodal Transportation Division.
Identification/Description; Photographs; Life Cycle; Habitat; Controls; Legal Aspects

Centaurea genus - EncycloWeedia
California Department of Food and Agriculture.
Identification/Description; Photographs; Habitat; Distribution; Dispersion; Controls

Spotted Knapweed
State of Colorado. Larimer County. Weed Control District.
Identification/Description; Photographs; Controls

Spotted Knapweed - Idaho's Noxious Weeds
Idaho Association of Soil Conservation Districts. Idaho OnePlan.
Identification/Description; Photographs; Introduction History; Distribution; Controls

Spotted Knapweed - Invasive Alien Plant Species of Virginia (PDF | 89 KB)
Virginia Department of Conservation and Recreation. Natural Heritage Program; Virginia Native Plant Society.
Identification/Description; Illustrations; Introduction History; Impacts; Habitat; Distribution; Controls

Spotted Knapweed Identification
State of Washington. King County Department of Natural Resources. Water and Land Resources Division.
Identification/Description; Photographs; Impacts

Spotted Knapweed
Washington State Noxious Weed Control Board.
Identification/Description; Photographs; Introduction History; Life Cycle; Habitat; Distribution; Controls; Special Note: References

Spotted Knapweed - Wisconsin Botanical Information System
Wisconsin State Herbarium; University of Wisconsin-Madison.
Taxonomy; Photographs; Habitat; Distribution

Spotted Knapweed
Wisconsin Department of Natural Resources.
Identification/Distribution; Photographs; Introduction History; Impacts; Habitat; Distribution; Controls

Spotted knapweed - Invasive Plant Species of Alaska (PDF | 88 KB)
University of Alaska - Anchorage. Alaska Natural Heritage Program.
Identification/Description; Photographs; Impacts; Habitat; Controls

Diffuse and Spotted Knapweed
Colorado State University. Cooperative Extension.
Identification/Description; Illustrations; Impacts; Life Cycle; Habitat; Distribution; Dispersion; Controls

Centaurea biebersteineii (Spotted knapweed) - Invasive Plant Atlas of New England (IPANE)
University of Connecticut. Ecology and Evolutionary Biology.
Taxonomy; Identification/Description; Photographs; Introduction History; Distribution; Dispersion; Controls

Centaurea maculosa (Spotted Knapweed)
University of Massachusetts - Boston. Biology Department. Conservation New England.
Identification/Description; Photograph; Introduction History; Life Cycle; Distribution; Dispersion; Special Note: Animation of the spread of Spotted Knapweed across Massachusetts over time

Montana Knapweeds: Identification, Biology, and Management
Montana State University. Extension Service.
Identification/Description; Photographs; Introduction History; Distribution; Controls

Spotted and Diffuse Knapweed - Noxious Weeds of Nebraska (PDF | 387 KB)
University of Nebraska - Lincoln. Cooperative Extension.
Identification/Description; Photographs; Introduction History; Life Cycle; Distribution; Dispersion; Controls

Spotted Knapweed Wanted Poster--Dead, Not Alive! (PDF | 163 KB)
University of Nevada - Reno. Cooperative Extension.
Identification/Description; Photographs

Spotted Knapweed - Introduced Species Summary Project
Columbia University. Center for Environmental Research and Conservation.
Taxonomy; Identification/Description; Photographs; Introduction History; Impacts; Life Cycle; Habitat; Controls

Know Your Knapweeds and Spotted Knapweed
North Dakota State University. Extension Service.
Identification/Description; Photographs; Introduction History; Distribution; Controls

Spotted Knapweed - Ohio Perennial & Biennial Weed Guide
Ohio State University. Ohio Agricultural Research and Development Center.
Identification/Description; Photographs; Introduction History

Spotted Knapweed - Invasive Plant Fact Sheets (PDF | 151 KB)
University of Pennsylvania. Morris Arboretum; Delaware River Invasive Plant Partnership.
Identification/Description; Photographs; Illustrations; Introduction History; Impacts; Habitat; Distribution; Dispersion; Controls

Spotted Knapweed - Guide to Weeds in British Columbia
British Columbia Ministry of Agriculture Food and Fisheries (Canada).
Identification/Description; Photographs; Illustrations; Impacts; Life Cycle; Habitat; Distribution; Dispersion; Controls

Spotted Knapweed
Royal British Columbia Museum (Canada); Okanagan University (Canada). Living Landscapes.
Identification/Description; Introduction History; Impacts; Habitat; Distribution; Dispersion; Controls

Centaurea biebersteinii (herb) - ISSG Global Invasive Species Database
World Conservation Union. Invasive Species Specialist Group.
Taxonomy; Identification/Description; Photographs; Impacts; Life Cycle; Habitat; Distribution; Controls

Spotted Knapweed
Colorado Weed Management Association.
Identification/Description; Photographs; Life Cycle; Habitat; Distribution; Dispersion

Centaurea biebersteinii
Discover Life.
Taxonomy; Identification/Description; Photographs; Illustrations; Impacts; Life Cycle; Habitat; Distribution; Dispersion; Controls

Spotted Knapweed
Invasive.org.
Photographs; Special Note: Resources

Spotted Knapweed
Montana Weed Control Association.
Identification/Description; Photographs; Introduction History; Impacts; Life Cycle; Habitat; Dispersion; Controls

Spotted Knapweed - BioBullies (PDF | 746 KB) (Western Pennsylvania)
Natural Biodiversity.
Identification/Description; Photographs; Introduction History; Impacts; Life Cycle; Habitat; Controls

Centaurea maculosa (Spotted Knapweed)
Nature Conservancy. Global Invasive Species Initiative.
Identification/Description; Photographs; Impacts; Life Cycle; Habitat; Distribution; Dispersion; Controls; Special Note: Weed Notes and Element Stewardship Abstract with excellent set of references

Spotted Knapweed
Plant Conservation Alliance. Alien Plant Working Group.
Identification/Description; Photographs; Introduction History; Impacts; Life Cycle; Habitat; Distribution; Controls; Special Note: References