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 napensis

HABIT Perennial; caespitose; clumped densely. Culms 20–60 cm long. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths open for most of their length. Ligule an eciliate membrane; 1 mm long; acute. Leaf-blades filiform; involute; 20–30 cm long; 1.5–2.5 mm wide. Leaf-blade surface scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; lanceolate; 3–8 cm long. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–4 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 6–7 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 lanceolate; 3 mm long; 0.85 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume elliptic; 3.5 mm long; 0.9 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; elliptic in profile; 4 mm long; membranous; keeled; 5 -veined. Lemma surface scaberulous, or scabrous; pubescent; hairy on veins. Lemma apex acute. Palea 1 length of lemma. Palea keels ciliolate; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION North America: southwest USA.

NOTES Poeae. Man Gr US 1994.

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