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.

Trisetum transcaucasicum

HABIT Perennial. Rhizomes elongated. Butt sheaths pilose. Culms 7–14 cm long. Leaves mostly basal. Ligule an eciliate membrane; 1.5–1.7 mm long; lacerate. Leaf-blades flat, or convolute; 1.5–2.6 cm long; 2.5 mm wide; glaucous. Leaf-blade surface pubescent; hairy on both sides. Leaf-blade margins ciliate. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong, or ovate; continuous, or interrupted; dense; 2–3 cm long; 0.8–1.5 cm wide. Primary panicle branches 1 -nate; bearing spikelets almost to the base.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 6–8 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pilose; with 3–4 mm long hairs.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny; gaping. Lower glume elliptic; 2–3 mm long; 0.5 length of upper glume; membranous; much thinner above; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume elliptic; 4–6 mm long; 0.9 length of adjacent fertile lemma; membranous; much thinner above; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 5–6 mm long; membranous; shiny; keeled; 5 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.66 way up back of lemma; geniculate; 5–6 mm long overall; with a straight or slightly twisted column. Palea gaping; hyaline.

FLOWER Anthers 3. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: Caucasus.

NOTES Aveneae. Seredin 1995.

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