Lachnagrostis robusta

HABIT Annual, or perennial; caespitose. Culms erect; 25–80 cm long; 2–3 -noded. Culm-internodes smooth. Culm-nodes glabrous. Leaf-sheaths smooth, or scaberulous. Ligule an eciliate membrane; 2–7 mm long; entire, or lacerate; obtuse. Leaf-blades involute, or convolute; 25–50 cm long; 1–8 mm wide.

INFLORESCENCE Inflorescence a panicle; deciduous as a whole; embraced at base by subtending leaf. Peduncle smooth; fracturing.

Panicle open; pyramidal; 12–25 cm long. Primary panicle branches whorled at lower nodes.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels clavate; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 3.5–5.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Spikelet callus base obtuse. Floret callus pilose.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 3.5–5.5 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 3.5–5.5 mm long; 1–1.4 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate; mucronate.

FLORETS Fertile lemma lanceolate; 2.5–5.5 mm long; hyaline; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface scaberulous; rough above; glabrous. Lemma apex dentate; 2–4 -fid; with lobes 0.3–1 mm long; truncate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.25–0.5 way up back of lemma; geniculate; 3.5–8 mm long overall; with twisted column. Palea 2–4 mm long; 0.9 length of lemma; hyaline. Palea apex dentate; 2 -fid. Rhachilla extension 2–3.5 mm long; pilose.

FLOWER Anthers 3; 0.4–1(–1.2) mm long.

DISTRIBUTION Australasia: Australia.

NOTES Aveneae. Fl Australia 2010.

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