Poa howellii
Howell's blue grass
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Family: Poaceae · Type: Grass · Native
Poa howellii (Howell's blue grass) is a native California grass in the Poaceae family, recognized by distinctive large spreading inflorescence with hairy lemma bodies.
Howell's blue grass is a California native annual grass found in the California Floristic Province (excluding southern Sierra Nevada, San Joaquin Valley, and Southern California) on rocky banks, shaded woodland slopes, and chaparral at elevations generally below 1,700 meters. Flowering from April to June, this grass produces delicate bluish-green flower clusters in loose, spreading panicles 20 to 25 centimeters long. Growing in dense tufts 30 to 80 centimeters tall with soft, flat leaf blades 1 to 6 millimeters wide, it forms compact clumps in disturbed and woodland habitats. Its leaf sheaths are partially open, with truncate to acute ligules 2.5 to 5 millimeters long, and each spikelet features lemmas with soft short hairs. The plant's tiny anthers and cobwebby flower bases add to its delicate woodland character.
Identification and appearance
Key characters: 47 sympatric species; distinctive large spreading inflorescence with hairy lemma bodies
Habitat and range
Habitat: Rocky banks, shaded slopes of woodland, chaparral, disturbed places
Elevation: generally < 1700 m
Outside California: to British Columbia
Bloom period
Poa howellii blooms Apr-Jun.
How to tell it apart
vs Festuca: Poa has boat-shaped, keeled leaf tips; Festuca leaves are flat or rolled but never keeled like a ship's prow.; vs Melica: Poa has fine, narrow leaves with boat-shaped tips; Melica has wider, flat leaves without the distinctive keel.; vs Nassella: Poa leaves have boat-shaped tips you can feel; Nassella leaves roll inward and lack the keel.; vs Koeleria: Poa has cobwebby hairs at seed base and keeled leaf tips; Koeleria lacks both features.; vs Holcus: Poa has boat-shaped leaf tips; Holcus leaves are flat and soft-hairy without any keel.
Frequently asked questions
Is Poa howellii native to California?
Yes. Poa howellii is native to California (recorded as native).
When does Poa howellii bloom?
Poa howellii blooms Apr-Jun.
What plant family does Poa howellii belong to?
Poa howellii is in the Poaceae family, genus Poa.
What habitat does Poa howellii grow in?
Poa howellii grows in Rocky banks, shaded slopes of woodland, chaparral, disturbed places.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.