Synonyms: Taeniatherum caput-medusae
Common names: medusahead
Elymus caput-medusae (medusahead) is a winter annual (family Poaceae) that typically invades disturbed sites, grasslands, openings in chaparral and oak woodlands. Taeniatherum caput-medusae out-competes native grasses and forbs and is found throughout northwestern California. After they set seed, medusahead plants persist as a dense litter layer that prevents germination and survival of native species, ties up nutrients, and contributes to fire danger in the summer.Cal-IPC Rating: High
Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.
Special ReportsMedusahead Management Guide for the Western States
Weed RIC Management Notes
- Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.
Cal-IPC Newsletter Articles
- Weed worker legend Joe DiTomaso retires. Brusati, Elizabeth. Vol 25, Issue 2
- One Tam unites around Marin’s mountain. Kesel, Rachel. Vol 24, Issue 3
- Native soil bacteria as biocontrol. Bean, Travis; Gornish, Elise. Vol 24, Issue 2
- Weeds and climate resilience in Sierra meadows. Brusati, Elizabeth; Johnson, Doug. Vol 24, Issue 1
- Wildland Weed News. Cal-IPC. Vol 22, Issue 3
- Prescribed grazing for invasive plant control on rangelands. Davy, Josh; Tate, Kenneth; Roche, Leslie. Vol 21, Issue 3
- Impacts of native vs. exotic grassland vegetation. Eviner, Valerie; Heraty, Joanne; Baty, Jill; Malmstrom, Carolyn; Rice, Kevin. Vol 21, Issue 3
- Partnering with college helps track medusahead. Alford, Jim; Benedetti, Daniel; Jennings, Nathan. Vol 20, Issue 3
- Jepson Manual 2nd ed. invasive plant name changes. Brusati, Elizabeth. Vol 20, Issue 2
- Exploring alternative methods for vegetation control and maintenance along roadsides. Young, Steve L.. Vol 10, Issue 4
Cal-IPC Symposium Presentations
Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.
- Grassland restoration and invasive weed management in Southern California: Medusahead as a case study. McDonald, Chris (2017)
- Plant community responses to cattle grazing in a noxious weed-dominated rangeland. Roche, Leslie; Tate, Ken (2016)
Other Elymus caput-medusae Information
- CalPhotos - Images of plants taken mostly in California.
- Calflora - See the distribution of this species on Calflora's map of California.
- Jepson Online Interchange for California Flora - Information on taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
- CDFA - California official noxious weeds.
- USDA PLANTS Database - Federal database with information on identification and distribution, and links to websites in individual states.
- Bugwood - National database from the Center for Invasive Species and Ecosystem Health at the University of Georgia.