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 grandis

HABIT Perennial; caespitose; clumped loosely. Rootstock evident. Culms erect; 50–120 cm long; 2–5 mm diam.; 5–12 -noded. Culm-internodes smooth. Culm-nodes swollen; pubescent. Lateral branches sparse. Leaf-sheaths tubular for much of their length; with 0.75 of their length closed; 6–9 cm long; keeled; glabrous on surface. Ligule an eciliate membrane; 2–6 mm long; glabrous on abaxial surface, or scaberulous on abaxial surface; truncate, or obtuse. Leaf-blades 7–25 cm long; 2–12 mm wide. Leaf-blade midrib keeled beneath. Leaf-blade surface smooth; glabrous, or puberulous; hairy adaxially. Leaf-blade margins smooth, or scaberulous. Leaf-blade apex hooded.

INFLORESCENCE Inflorescence a panicle.

Panicle open; pyramidal; effuse; 15–35 cm long; 10–20 cm wide. Primary panicle branches spreading, or reflexed; 2–9 -nate; 6–12 cm long; bearing 7–26 fertile spikelets on each lower branch. Panicle axis with lower internodes 3–8 cm long. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–5 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.3–1 mm long; smooth, or scaberulous; glabrous, or sparsely hairy. Floret callus glabrous, or woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate, or ovate; 2.3–4 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 lanceolate, or ovate; 3.5–5 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume surface papillose. Upper glume apex acute.

FLORETS Fertile florets bisexual, or female. Fertile lemma lanceolate, or elliptic; 3.5–5 mm long; membranous; keeled; 5 -veined. Lemma midvein ciliolate; hairy above. Lemma surface scabrous. Lemma margins ciliolate; hairy above. Lemma apex acute. Palea keels scabrous; eciliate, or ciliolate; adorned in the middle. Palea surface scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1.8–2.8 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: China. Asia-tropical: Indo-China.

NOTES Poeae. Fl China 2005.

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