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 hakusanensis

HABIT Perennial; caespitose; clumped loosely. Rhizomes short. Culms erect; 35–70 cm long; 0.8–1.5 mm diam.; 2–3 -noded. Leaf-sheaths tubular for much of their length; with 1 of their length closed; without keel; smooth. Ligule an eciliate membrane; 1 mm long; truncate. Leaf-blades 10–20 cm long; 2–6 mm wide. Leaf-blade margins smooth. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 8–16 cm long; 3.5–9 cm wide. Primary panicle branches 2–4 -nate; 3–6 cm long. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with diminished florets at the apex. Spikelets elliptic, or ovate; laterally compressed; 5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes smooth. Floret callus woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 3.5–3.7 mm long; 0.75–0.9 length of upper glume; membranous; 1-keeled; 1–3 -veined. Lower glume lateral veins absent, or obscure. Lower glume apex acute. Upper glume lanceolate; 3.8–4.8 mm long; 0.75–0.9 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume surface scabrous; rough on veins. Upper glume apex acute.

FLORETS Fertile lemma ovate; elliptic in profile; 5–5.2 mm long; membranous; keeled; 5 -veined. Lemma midvein pubescent; hairy at base. Lemma surface pubescent; hairy at base; hairy on veins. Lemma apex acute. Palea keels scaberulous; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: eastern Asia.

NOTES Poeae. Koyama 1994.

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