Elymus glaucus
Blue or western wild-rye, Western Wild-Rye
Photo by Chez Brungraber
Family: Poaceae · Type: Grass · Native
Elymus glaucus (Blue or western wild-rye) is a native California grass in the Poaceae family, recognized by Tufted perennial wild-rye; slender persistent spike (not disarticulating), spikelets ~2 per node, glumes only short-awned.
Blue or western wild-rye is a native perennial grass found in diverse California bioregions, including coastal, Sierra Nevada, and Cascade Mountains, in grasslands, meadows, and open woodlands at elevations ranging from low to mid-elevation zones. Flowering from May to July, this grass produces pale green to bluish-green spikelets with delicate, divergent awns in compact, erect or slightly nodding seed heads. Growing 3 to 4.5 meters tall with slender, sometimes short-rhizomed stems, it forms dense, upright clumps with graceful, arching leaves. Its leaves are flat, 4 to 12 millimeters wide, with short auricles and ligules less than 1 millimeter long, presenting a fine-textured, soft green appearance. The grass bears spikelets with 2 to 4 florets, featuring glumes 6.5 to 19 millimeters long that are generally short-awned, creating an elegant, wave-like profile in grassland landscapes.
Identification and appearance
Key characters: Tufted perennial wild-rye; slender persistent spike (not disarticulating), spikelets ~2 per node, glumes only short-awned.
Habitat and range
California counties: Humboldt, Calaveras, Ventura, El Dorado, Los Angeles, Inyo, San Luis Obispo, Plumas, Marin, Mendocino, Placer, Riverside, Tulare, Mariposa, Del Norte, Sutter, San Bernardino, Lake, Solano, Fresno, Sonoma, Orange, Kern, Monterey, Napa, Amador, Santa Cruz, Siskiyou, Trinity, Nevada, Sierra, Santa Clara, Butte, San Mateo, San Francisco, Tuolumne, Modoc, Alpine, Contra Costa, San Diego, Santa Barbara, Madera, Shasta, Colusa, Sacramento, Yuba, Alameda, Lassen, Glenn, Tehama, Stanislaus, Merced, San Benito, Yolo, San Joaquin, Mono
How to tell it apart
vs Hordeum: Elymus has rounded glume backs; Hordeum has all glumes narrow and bristle-like.; vs Leymus: Elymus has 2-8 spikelets per node; Leymus has just 1-2 spikelets per node.; vs Taeniatherum: Elymus is perennial with robust growth; Taeniatherum is a weedy annual with very long awns.; vs Lolium: Elymus shows multiple spikelets per node; Lolium has single spikelets edgewise to the stem.; vs Thinopyrum: Elymus has prominent auricles; Thinopyrum typically lacks auricles or has very small ones.
Frequently asked questions
Is Elymus glaucus native to California?
Yes. Elymus glaucus is native to California (recorded as native).
Where in California does Elymus glaucus grow?
Elymus glaucus occurs in Humboldt, Calaveras, Ventura, El Dorado, Los Angeles, Inyo, San Luis Obispo, Plumas and other counties.
What plant family does Elymus glaucus belong to?
Elymus glaucus is in the Poaceae family, genus Elymus.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.