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 ursina

HABIT Perennial; caespitose; clumped loosely. Butt sheaths persistent and investing base of culm. Basal innovations intravaginal. Culms erect; 20–30 cm long. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 1–2.5 mm long; lacerate; obtuse. Leaf-blades flat, or conduplicate; 4–9 cm long; 1–1.5 mm wide. Leaf-blade margins unthickened. Leaf-blade apex abruptly acute.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; elliptic; 3.5–5 cm long. Primary panicle branches 2 -nate.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous, or woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 0.8–0.9 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; 3–3.5 mm long; membranous; keeled; 5 -veined. Lemma midvein ciliolate. Lemma margins ciliolate. Lemma apex acute. Palea keels ciliate; adorned below. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1.6 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Europe: southeastern and eastern.

NOTES Poeae. Fl Eur 1995.

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