Poa abbreviata ssp. pattersonii

General:
Perennial, densely tufted grass from fibrous roots; stems 5-15 (20) cm tall.

Leaves:
Sheath margins open 3/4-9/10 their length; sterile shoots emerging inside sheaths; basal bladeless leaves absent; blades 0.8-1.5 (2) mm wide, in-rolled, moderately thick; ligules 0.8-5.5 mm long, the tips rounded to sharp-pointed, the backs smooth or rough.

Flowers:
Inflorescence an erect panicle, 1.5-5 cm long, lanceolate to egg-shaped, congested, the branches 1 to 3 per node, appressed, slender, to 1.5 cm long, smooth to slightly rough on angles; spikelets laterally compressed, 4-6.5 mm long, 2- to 5-flowered, frequently strongly purplish, longer than stalks; glumes lanceolate to broadly lanceolate, smooth, nearly equalling to slightly longer than adjacent lemmas, the lower 1-nerved; rachilla internodes usually less than 1 mm long, smooth to rough; lemmas broadly lanceolate, 3-4.6 mm long, the tips sharp-pointed, keels (to 3/4 the length) and marginal nerves soft-hairy, hairless or minutely soft-hairy between the nerves; calluses hairless or cobwebby; palea keels rough, medially often minutely soft to short silky-hairy; flowers bisexual (sometimes with bulbils); anthers 0.6-1.2 (1.8) mm long.

Source:  The Illustrated Flora of British Columbia