Poa laxa

HABIT Perennial; caespitose; clumped densely. Basal innovations extravaginal. Culms erect; 13–20 cm long. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface. Ligule an eciliate membrane; 2–3 mm long; entire, or lacerate; acute. Leaf-blades 0.8–1.5 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate, or oblong; 2.8–3.5 cm long. Panicle branches channelled; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–4 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 5–5.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes smooth. Floret callus woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; elliptic in profile; 3 mm long; membranous; keeled; 5 -veined. Lemma midvein ciliate. Lemma surface pubescent; hairy on veins. Lemma margins ciliate; hairy all along. Lemma apex acute. Palea keels scabrous; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1–1.3 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Europe: central, southwestern, and southeastern. North America: Subarctic, eastern Canada, and northeast USA.

NOTES Poeae. Fl Eur 1995.

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