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 vaginata

HABIT Perennial; caespitose. Rhizomes short. Butt sheaths thickened and forming a bulb. Culms erect, or geniculately ascending; 6–7 cm long; 1 -noded. Culm-internodes unequal, the upper longer; terete; smooth. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths longer than adjacent culm internode. Ligule an eciliate membrane; 3–6 mm long; acuminate. Leaf-blades filiform; convolute; 3–4 cm long; 0.5 mm wide.

INFLORESCENCE Inflorescence a panicle; embraced at base by subtending leaf.

Panicle open; lanceolate; dense; 2–2.5 cm long. Primary panicle branches 1–2 -nate. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 5–6 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 5 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 ovate; 0.8–0.9 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein scabrous. Lower glume apex acuminate. Upper glume ovate; 0.9–1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume apex acuminate.

FLORETS Fertile lemma ovate; 3 mm long; membranous; keeled; 5 -veined. Lemma midvein ciliate. Lemma margins ciliate; hairy below. Lemma apex obtuse. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Africa: north.

NOTES Poeae. Fl Libya 1997.

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