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 unilateralis

HABIT Perennial; caespitose; clumped densely. Butt sheaths papery. Culms geniculately ascending, or decumbent; 10–40 cm long. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane. Leaf-blades flat, or conduplicate; 2–8 cm long; 1–3 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; oblong; 2–6 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–4 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 6–8 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous, or pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 2–3 mm long; 1 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume ovate; 2–3 mm long; 0.66–0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; 3–4 mm long; membranous; keeled; 5 -veined. Lemma apex acute. Palea 1 length of lemma. Palea keels scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION North America: northwest USA and southwest USA.

NOTES Poeae. Man US Gr 1994.

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