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 drummondiana

HABIT Perennial. Rhizomes short. Butt sheaths herbaceous; thickened and forming a bulb. Culms erect, or geniculately ascending; 25–80 cm long; 2–3 -noded; swollen at the base; forming an ovoid corm. Culm-internodes terete; smooth. Culm-nodes glabrous. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths loose; smooth; glabrous on surface. Ligule an eciliate membrane; 2–6 mm long; glabrous on abaxial surface, or scaberulous on abaxial surface; obtuse. Leaf-blades flat, or conduplicate; 8–30 cm long; 2–4 mm wide. Leaf-blade surface ribbed; scabrous; rough on both sides.

INFLORESCENCE Inflorescence a panicle. Peduncle smooth, or scaberulous above.

Panicle open; lanceolate, or pyramidal; 10–20 cm long. Primary panicle branches ascending, or spreading; 2–5 -nate; sparsely divided; 5–11 cm long. Panicle branches capillary; scabrous.

Spikelets pendulous; solitary. Fertile spikelets pedicelled. Pedicels 2–12 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 3–8 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; compressed slightly; 7–12 mm long; 6–10 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.6 mm long; smooth. Floret callus glabrous.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume oblong; 2.5–5 mm long; 0.75–0.9 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein smooth, or scabrous. Lower glume apex obtuse, or acute. Upper glume oblong; 3–6 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3–5 -veined. Upper glume primary vein smooth, or scabrous. Upper glume apex obtuse, or acute.

FLORETS Fertile lemma oblong; ovate in profile; 3–6 mm long; membranous; much thinner above; keeled; lightly keeled; 5 -veined. Lemma midvein eciliate, or ciliate; hairy below. Lemma surface pubescent; hairy on veins. Lemma margins ciliate. Lemma apex truncate, or obtuse. Palea 0.9 length of lemma. Palea keels scaberulous; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 2.2–3 mm long; yellow.

FRUIT Caryopsis with adherent pericarp; oblong; trigonous; 5 mm long. Embryo 0.2 length of caryopsis. Hilum punctiform.

DISTRIBUTION Australasia: Australia.

NOTES Poeae. Vickery.

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