Erioneuron pilosum
Hairy erioneuron
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Family: Poaceae · Type: Grass · Native
Conservation status: CNPS 2B.3
Erioneuron pilosum (Hairy erioneuron) is a native California grass in the Poaceae family, recognized by Small genus of southwestern North America adapted to rocky desert conditions; specialized niche within grass family.
Hairy erioneuron is a California native perennial found in the eastern Mojave Desert Mountains in rocky pinyon and juniper woodland at elevations of 1,280 to 2,000 meters. Flowering from May to June, this grass produces tan to purple-tinged spikelets in compact raceme-like clusters 1.5 to 4 centimeters long. Growing in dense clumps with erect stems 10 to 30 centimeters tall, it forms tufted bunches with distinctive characteristics. Its leaves are narrow, 3 to 6 centimeters long and only 1 to 1.5 millimeters wide, with white margins and soft hairy sheaths at the collar. The plant's delicate spikelets feature lemmas with tiny 2-toothed tips and short awns measuring 0.5 to 2.5 millimeters long.
Identification and appearance
Key characters: Small genus of southwestern North America adapted to rocky desert conditions; specialized niche within grass family
Habitat and range
Habitat: Rocky slopes, ridges, pinyon/juniper woodland
Elevation: 1280-2000 m
California counties: San Bernardino, San Diego
Outside California: to Kansas, Texas, Mexico
Bloom period
Erioneuron pilosum blooms May-Jun.
Conservation status
CNPS 2B.3
Frequently asked questions
Is Erioneuron pilosum native to California?
Yes. Erioneuron pilosum is native to California (recorded as native).
When does Erioneuron pilosum bloom?
Erioneuron pilosum blooms May-Jun.
Where in California does Erioneuron pilosum grow?
Erioneuron pilosum occurs in San Bernardino, San Diego, at elevations of 1280-2000 m.
What plant family does Erioneuron pilosum belong to?
Erioneuron pilosum is in the Poaceae family, genus Erioneuron.
Is Erioneuron pilosum rare or endangered?
Erioneuron pilosum carries California Rare Plant Rank 2B.3, state rank S2.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.