Trisetum debile

HABIT Perennial; caespitose. Culms erect; 25 cm long; 0.8 mm diam.; 3 -noded. Culm-internodes smooth; distally glabrous, or pubescent. Leaf-sheaths 5.5 cm long; puberulous. Ligule an eciliate membrane; 0.7 mm long. Leaf-blades 4 cm long; 1–1.2 mm wide. Leaf-blade surface puberulous; hairy on both sides. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle. Peduncle pilose above.

Panicle open; lanceolate; 4 cm long; 0.5 cm wide; bearing few spikelets. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with diminished florets at the apex. Spikelets oblong, or cuneate; laterally compressed; 5–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent.

GLUMES Glumes persistent; dissimilar; shorter than spikelet; thinner than fertile lemma; gaping. Lower glume lanceolate; 3–4 mm long; 0.75–0.8 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins obscure. Lower glume apex acuminate; mucronate. Upper glume lanceolate; 4–4.5 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 5 -veined. Upper glume primary vein obscure; scaberulous. Upper glume apex acuminate; mucronate.

FLORETS Fertile lemma lanceolate; 4–4.5 mm long; chartaceous; keeled; 5 -veined. Lemma midvein scaberulous. Lemma lateral veins obscure. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.66 way up back of lemma; curved, or geniculate; 5–7 mm long overall; without a column, or with a straight or slightly twisted column. Palea 4.5 mm long; hyaline. Palea keels ciliate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3. Ovary pubescent on apex.

DISTRIBUTION Asia-temperate: China.

NOTES Aveneae. Chrtek 2006.

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