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Medusahead - Photo by Steve Dewey; Utah State University
Scientific Name: 
Taeniatherum caput-medusae (L.) Nevski (ITIS)
Elymus caput-medusae L.; Taeniatherum asperum(Simonkai) Nevski; Hordeum caput-medusae (L.) Crosson & Durand (ITIS)
Common Name: 
Medusahead, medusa's head, medusahead rye, medusahead grass
Native To: 
Mediterranean Region (Archer 2001)
Date of U.S. Introduction: 
First discovered in 1887 (DiTomaso et al. 2008)
Means of Introduction: 
Introduced as a seed contaminant (DiTomaso et al. 2008)
Crowds out native species and forage for livestock (Archer 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.


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 Medusahead.

Council or Task Force

Alberta Invasive Plant 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

California Invasive Plant Council.

In online book: Bossard, C.C., J.M. Randall, and M.C. Hoshovsky (Editors). 2000. Invasive Plants of California's Wildlands. University of California Press. Berkeley, CA

Sage Grouse Initiative. Great Basin Factsheet Series.

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

DOI. USGS. Forest and Rangeland Ecosystem Science Center.

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
Plumas-Sierra Noxious Weeds Management Group (California).
See also: Agricultural Brochures for more species
California Department of Food and Agriculture.
See also: Included on California's noxious weed list; see Encycloweedia: Program Details for additional resources

Wisconsin Department of Natural Resources.

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


Montana State University Extension.

University of California. Weed Research and Information Center.

Washington State University. Whitman County Extension.

University of Nebraska - Lincoln. Institute of Agriculture and Natural Resources.

Colorado Weed Management Association.