Hordeum marinum subsp. gussoneanum
Mediterranean barley, Mediterranean Barley
Jose Hernandez @ USDA-NRCS PLANTS Database (via Wikimedia Commons) · CC0
Family: Poaceae · Type: Grass · Not Native
Conservation status: Cal-IPC Yes
Hordeum marinum subsp. gussoneanum (Mediterranean barley) is a non-native California grass in the Poaceae family, recognized by spikelets falling together as units and non-flattened glume bases.
Mediterranean barley is a naturalized annual grass found in California (except the southeastern deserts) in dry to moist disturbed sites at elevations below 1,800 meters. Flowering from April to June, this plant produces green to purple inflorescences 1.5 to 7 centimeters long with distinctive bristly spikelets. Growing 10 to 50 centimeters tall with stems that are bent at the base or erect, it has a characteristic growth habit in disturbed landscapes. Its leaf blades reach up to 8 centimeters long and 1 to 6 millimeters wide, with slightly hairy basal sheaths. The plant's central and lateral spikelets fall together, with glumes 10 to 26 millimeters long and conspicuous awns measuring 3 to 18 millimeters.
Identification and appearance
Key characters: 10 sympatric species; key feature is spikelets falling together as units and non-flattened glume bases
Habitat and range
Habitat: dry to moist, disturbed sites
Elevation: < 1800 m
California counties: El Dorado, San Luis Obispo, Riverside, Calaveras, Monterey, Lake, Merced, Santa Barbara, Napa, Alameda, Orange, Ventura, Marin, Humboldt, San Diego, Fresno, Sonoma, Kern, San Joaquin, Mendocino, Contra Costa, Los Angeles, Colusa, San Bernardino, Siskiyou, Yuba, Glenn, Tulare, Yolo, Sutter, Inyo, Modoc, Madera, Mariposa, Placer, Sacramento, San Benito, Sierra, Solano, Stanislaus, Trinity, Butte, Lassen, Nevada, Plumas, San Francisco, San Mateo, Santa Clara, Santa Cruz, Tuolumne, Amador, Tehama, Kings, Shasta, Del Norte, Alpine
Outside California: to British Columbia, Montana, Oklahoma, Arizona, scattered in eastern United States, native to Mediterranean
Bloom period
Hordeum marinum subsp. gussoneanum blooms Apr-Jun.
Conservation status
Cal-IPC Yes
How to tell it apart
vs Bromus: Hordeum has three spikelets per node in a spike; Bromus has separate spikelets in loose clusters.; vs Triticum: Hordeum has three spikelets per node; Triticum has one spikelet per node.; vs Taeniatherum: Hordeum has the central spikelet stalkless; check if side spikelets are stalked.; vs Setaria: Hordeum has three grouped spikelets per node; Setaria has dense bristly single spikelets.; vs Elymus: Hordeum has hollow stems; Elymus has solid stems between nodes.
Frequently asked questions
Is Hordeum marinum subsp. gussoneanum native to California?
No. Hordeum marinum subsp. gussoneanum is not native to California (recorded as not native).
When does Hordeum marinum subsp. gussoneanum bloom?
Hordeum marinum subsp. gussoneanum blooms Apr-Jun.
Where in California does Hordeum marinum subsp. gussoneanum grow?
Hordeum marinum subsp. gussoneanum occurs in El Dorado, San Luis Obispo, Riverside, Calaveras, Monterey, Lake, Merced, Santa Barbara and other counties, at elevations of < 1800 m.
What plant family does Hordeum marinum subsp. gussoneanum belong to?
Hordeum marinum subsp. gussoneanum is in the Poaceae family, genus Hordeum.
Is Hordeum marinum subsp. gussoneanum invasive in California?
Hordeum marinum subsp. gussoneanum is listed by Cal-IPC with an invasiveness rating of Yes.
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.