Poa stenantha

HABIT Perennial; caespitose. Culms 25–60 cm long. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths open for most of their length; with 0.25 of their length closed; smooth. Ligule an eciliate membrane; 1.5–3.5 mm long; pubescent on abaxial surface; lacerate; acute. Leaf-blades flat, or involute; 1–2 mm wide; flaccid.

INFLORESCENCE Inflorescence a panicle.

Panicle open; pyramidal; nodding; 7–15 cm long. Primary panicle branches spreading, or drooping; 2–3 -nate.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 6–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes smooth. Floret callus glabrous.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 3–4 mm long; 0.75 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume elliptic; 4–5.5 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; 4–6 mm long; membranous; keeled; 5 -veined. Lemma midvein ciliate. Lemma surface puberulous; hairy between veins. Lemma margins ciliate. Lemma apex acute. Palea 1 length of lemma. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1.2–2 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION North America: Subarctic, western Canada, and northwest USA. South America: southern South America.

NOTES Poeae. Fl Pac NW 1994.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.