Nassella leucotricha

HABIT Perennial; caespitose; clumped densely. Cataphylls inconspicuous. Culms erect, or decumbent (slightly); 20–50 cm long; 1.5–3 mm diam.; without nodal roots. Culm-internodes ridged; distally glabrous. Culm-nodes pubescent. Leaves basal and cauline; differentiated into sheath and blade. Leaf-sheaths smooth to scaberulous; outer margin glabrous to hairy. Leaf-sheath oral hairs pubescent. Leaf-sheath auricles erect; 1–2 mm long. Ligule an eciliate membrane; 0.4–0.7 mm long; truncate. Leaf-blades flat, or involute; 10–30 cm long; 2–5 mm wide. Leaf-blade surface ribbed; glabrous, or pubescent; sparsely hairy; hairy on both sides. Leaf-blade apex filiform.

INFLORESCENCE Bisexual. Synflorescence simple. Inflorescence a panicle.

Panicle contracted; 15 cm long; 1–3 cm wide; bearing few spikelets. Primary panicle branches ascending, or spreading; 2 -nate. Panicle branches angular; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels angular.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets. Spikelets elliptic; laterally compressed; 10–17 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 1.2–3.3 mm long; pilose.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 10–17 mm long; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume surface glabrous, or puberulous; hairy on veins. Lower glume apex acute, or acuminate. Upper glume lanceolate; 10–16 mm long; 1.5–1.8 length of adjacent fertile lemma; membranous; without keels; 3(–5) -veined. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma linear; subterete; 5.3–5.7 mm long; coriaceous; without keel; rounded throughout. Lemma surface granulose; pubescent; hairy in the middle. Lemma margins convolute; covering most of palea. Lemma apex emarginate, or truncate; with a membranous corona; with this appendage 1.5–2.5 mm long; awned; 1 -awned. Principal lemma awn bigeniculate; 50–60 mm long overall; with twisted column; limb scaberulous. Column of lemma awn 20–30 mm long; with 0.8 mm long hairs. Palea elliptic; 0.35–0.5 length of lemma; membranous; 0 -veined; without keels. Palea surface smooth; glabrous.

FLOWER Lodicules 2; oblong; membranous. Anthers 3. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; fusiform. Embryo 0.2–0.35 length of caryopsis. Hilum linear.

DISTRIBUTION Australasia: Australia. North America: north-central USA, south-central USA, and Mexico.

NOTES Stipeae. TB.

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