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 sieberiana

HABIT Perennial; caespitose; clumped densely. Rootstock evident. Butt sheaths herbaceous; pallid. Basal innovations intravaginal. Culms 15–80 cm long. Culm-internodes terete; smooth. Lateral branches lacking. Leaf-sheaths smooth, or scaberulous; glabrous on surface. Ligule a ciliolate membrane; 0.1–1 mm long; scaberulous on abaxial surface; truncate. Leaf-blades straight, or curved, or flexuous; filiform; involute; 5–60 cm long; 0.2–0.7 mm wide; glaucous, or grey-green. Leaf-blade surface scabrous; rough on both sides; glabrous, or hirsute. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle. Peduncle smooth.

Panicle open; pyramidal; 3–20 cm long. Primary panicle branches 1–5 -nate; sparsely divided. Panicle branches flexible, or capillary; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 2–7 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 5–8 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes smooth. Floret callus glabrous, or woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 0.9 length of upper glume; membranous; 1-keeled; 1–3 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent, or obscure. Lower glume surface smooth, or asperulous. Lower glume apex acute. Upper glume ovate; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume surface smooth, or asperulous. Upper glume apex acute.

FLORETS Fertile lemma ovate; lanceolate in profile, or oblong in profile; 1.8–3 mm long; membranous; keeled; 5 -veined. Lemma midvein eciliate, or ciliate. Lemma surface pubescent; hairy below. Lemma margins eciliate, or ciliate. Lemma apex obtuse. Palea 0.9 length of lemma. Palea keels scabrous; eciliate, or ciliolate; adorned below (ciliolate). Palea surface pubescent. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1–2 mm long; yellow, or purple.

FRUIT Caryopsis with adherent pericarp; oblong; 1.5 mm long. Hilum punctiform.

DISTRIBUTION Australasia: Australia and New Zealand.

NOTES Poeae. Vickery.

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