Poa piperi
Piper's blue grass
Family: Poaceae · Type: Grass · Native
Conservation status: CNPS 4.3
Poa piperi (Piper's blue grass) is a native California grass in the Poaceae family, recognized by no sympatric species.
Piper's blue grass is a California native perennial found in the northwestern Klamath Ranges in Del Norte County, specifically in serpentine, talus, chaparral, and forest openings at elevations of 100 to 500 meters. Flowering from April to June, this grass produces sparse, delicate inflorescences with small spikelets. Growing in tufted clusters 20 to 55 centimeters tall, it spreads through underground rhizomes with firm, narrow blades that are folded and inrolled. Its leaves have distinctive features, with open sheaths and short ligules measuring 1 to 2 millimeters, and sterile stem blades with fine hairs on the upper surface. The plant is dioecious, with unisexual flowers and spikelets featuring diffusely cobwebby calluses.
Identification and appearance
Key characters: Geographically isolated; no sympatric species
Habitat and range
Habitat: Serpentine, talus, chaparral, forest openings
Elevation: 100-500 m
California counties: Del Norte, Siskiyou
Outside California: to southwestern Oregon
Bloom period
Poa piperi blooms Apr-Jun.
Conservation status
CNPS 4.3
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 piperi native to California?
Yes. Poa piperi is native to California (recorded as native).
When does Poa piperi bloom?
Poa piperi blooms Apr-Jun.
Where in California does Poa piperi grow?
Poa piperi occurs in Del Norte, Siskiyou, at elevations of 100-500 m.
What plant family does Poa piperi belong to?
Poa piperi is in the Poaceae family, genus Poa.
Is Poa piperi rare or endangered?
Poa piperi carries California Rare Plant Rank 4.3, state rank S3.
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 2026-10-08
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.