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Scientific Name

Taeniatherum caput-medusae (L.) Nevski (ITIS)

Common Name

Medusahead, medusa's head, medusahead rye, medusahead grass


Elymus caput-medusae L.; Taeniatherum asperum(Simonkai) Nevski; Hordeum caput-medusae (L.) Crosson & Durand (ITIS)

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)

Image use policy



Photo by Steve Dewey; Utah State University

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  • The Greening of the Great Basin

    • Dec 28, 2022
    • JSTOR Daily.

    • The arid and semiarid Great Basin of the western United States comprises parts of California, Nevada, Utah, Idaho, and Oregon and can variously be described by its hydrology, topography, or biology. Biologically, the area has been defined historically by the native sagebrush and shrubs that thrive in the dry valleys of the Sierra Nevada and Cascade Mountains. But, as a recent study undertaken by researchers at the University of Montana and the Department of Agriculture notes, these native plant communities are rapidly being colonized by nonnative annual grasses like cheatgrass (Bromus tectorum), red brome (B. rubens), and medusahead (Taeniatherum caput-medusae) to the detriment of wildlife and humans.

Distribution / Maps / Survey Status


Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Council or Task Force
Federal Government
State and Local Government