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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
Medusahead - Photo by Steve Dewey; Utah State University
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



Selected Resources

The section below contains selected highly relevant resources for this species, organized by source. To view all related content for this species, click on "View all resources for species" in the top left of this page.

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


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

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

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.


Washington State University. Whitman County Extension.


Colorado Weed Management Association.
Wallowa Resources (Oregon).
See also: Top Ten Weeds in Wallowa County for more fact sheets