GrassBase - The Online World Grass Flora


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

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

Poa nubigena

HABIT Perennial; caespitose; clumped densely. Rhizomes absent. Basal innovations intravaginal. Culms 30–65 cm long; 1 mm diam.; 2–3 -noded; with 2–3 of their length below uppermost node. Culm-internodes smooth. Lateral branches lacking. Leaf-sheaths loose; open for most of their length; with 0.4–0.6 of their length closed; 4.5–12 cm long; keeled; smooth, or scaberulous; glabrous on surface. Leaf-sheath oral hairs scanty, or lacking. Ligule an eciliate membrane; 2–4.1 mm long; 0.5 mm long on basal shoots; glabrous on abaxial surface; obtuse, or acute. Leaf-blades flat, or conduplicate; 3–11 cm long; 1–2 mm wide. Leaf-blade surface scabrous; rough adaxially. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; pyramidal; effuse; 5.5–14 cm long; 3–8 cm wide. Primary panicle branches spreading; 2 -nate; 3–7.5 cm long; bearing 3–11 fertile spikelets on each lower branch. Panicle axis with lower internodes 2–3.5 cm long. Panicle branches flexuous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 3.5–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.2 mm long; scaberulous. Floret callus woolly.

GLUMES Glumes persistent; similar; with lower narrower than upper; shorter than spikelet. Lower glume oblong, or ovate; 2.3–3.5 mm long; 0.75 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein smooth to scabrous. Lower glume lateral veins absent, or obscure. Lower glume apex acuminate. Upper glume oblong, or ovate; 2.7–4.5 mm long; 0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume lateral veins obscure. Upper glume surface papillose. Upper glume apex acute.

FLORETS Fertile florets bisexual, or female. Fertile lemma lanceolate; 3.5–5.2 mm long; membranous; keeled; 5 -veined. Lemma midvein ciliate; hairy above. Lemma surface scaberulous, or papillose. Lemma apex acute. Palea keels scabrous. Palea surface scabrous. Apical sterile florets resembling fertile though underdeveloped.

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

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: China.

NOTES Poeae. Fl China 2005.

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