Poa abbreviata subsp. pattersonii
Patterson's blue grass, Patterson's Blue Grass
Photo: parent species Poa abbreviata · (c) Trevor Van Loon, some rights reserved (CC BY) · licence
Family: Poaceae · Type: Grass · Native
Conservation status: CNPS 2B.3
Poa abbreviata subsp. pattersonii (Patterson's blue grass) is a native California grass in the Poaceae family, recognized by cobwebby callus and hairy lemma features.
Patterson's blue grass is a rare (CNPS 2B.3) California native perennial found in the Sierra Nevada Mountains and White Mountains in high alpine open ground at elevations generally above 3,300 meters. Flowering in July, this plant produces small, delicate blue-green grass flowers in compact clusters. Growing with fine, clustered stems up to 30 centimeters tall, it forms dense tufted mats in harsh alpine environments. Its leaves feature short ligules 1 to 3.5 millimeters long, with lemma keels and marginal veins that are notably hairy. The plant's delicate structure and adaptation to extreme high-elevation conditions make it a distinctive alpine grass species.
Identification and appearance
Key characters: 30 sympatric species; distinguished by cobwebby callus and hairy lemma features
Habitat and range
Habitat: High alpine open ground
Elevation: generally > 3300 m
Outside California: Alaska to New Mexico, Far East Russia
Bloom period
Poa abbreviata subsp. pattersonii blooms Jul.
Conservation status
CNPS 2B.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 abbreviata subsp. pattersonii native to California?
Yes. Poa abbreviata subsp. pattersonii is native to California (recorded as native).
When does Poa abbreviata subsp. pattersonii bloom?
Poa abbreviata subsp. pattersonii blooms Jul.
What plant family does Poa abbreviata subsp. pattersonii belong to?
Poa abbreviata subsp. pattersonii is in the Poaceae family, genus Poa.
Is Poa abbreviata subsp. pattersonii rare or endangered?
Poa abbreviata subsp. pattersonii carries California Rare Plant Rank 2B.3, state rank S1.
What habitat does Poa abbreviata subsp. pattersonii grow in?
Poa abbreviata subsp. pattersonii grows in High alpine open ground.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.