GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Poa longifolia

HABIT Perennial; caespitose; clumped densely. Butt sheaths herbaceous; persistent and investing base of culm. Culms 30–60(–100) cm long. Culm-internodes terete; smooth. Culm-nodes glabrous. Lateral branches lacking. Leaves mostly basal. Ligule an eciliate membrane; 1–2 mm long; acute. Leaf-blades involute; 10–20 cm long; (1.5–)2–4.5 mm wide; 5 cm long at summit of culm (and erect). Leaf-blade margins scaberulous. Leaf-blade apex abruptly acute; apiculate.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; elliptic; 7–15 cm long. Primary panicle branches 2–4 -nate. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; (5–)7–8 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes smooth. Floret callus glabrous.

GLUMES Glumes persistent; similar; subequal in width; shorter than spikelet. Lower glume lanceolate; 3.5 mm long; 0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume oblong; 3 mm long; 0.9 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; elliptic in profile; 4.5 mm long; membranous; keeled; 5 -veined. Lemma surface glabrous. Lemma apex acute. Palea 0.9 length of lemma. Palea keels scabrous; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 2.5–3.5 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Europe: eastern. Asia-temperate: Caucasus and western Asia.

NOTES Poeae. Fl Turk.

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