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 tianschanica

HABIT Perennial; caespitose; clumped densely. Stolons present. Culms geniculately ascending; 10–70 cm long. Culm-internodes terete; purple; distally pruinose, or glabrous. Lateral branches lacking. Leaf-sheaths tubular for much of their length; with 0.5 of their length closed; smooth; glabrous on surface. Ligule an eciliate membrane; 0.25–3 mm long; obtuse. Leaf-blades flat, or conduplicate; 2–5 mm wide; grey-green. Leaf-blade surface scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong, or pyramidal; 5–12 cm long; 3–5 cm wide. Primary panicle branches 4–5 -nate. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–6 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 4–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 3.5 mm long; 1 length of upper glume; membranous; purple; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 3.5 mm long; 1 length of adjacent fertile lemma; membranous; purple; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; 3.5 mm long; membranous; purple; keeled; 5 -veined. Lemma lateral veins prominent. Lemma surface pubescent; hairy below; hairy on veins. Lemma apex acute. Palea 1 length of lemma. Palea keels scabrous; with 10–20 enations per keel. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: Siberia, Soviet Middle Asia, China, and Mongolia.

NOTES Poeae. Fl USSR 1996.

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