Lachnagrostis elata

Detailed description

Grey-green to grass green, slender, tufted perennial grass producing 1-many, somewhat laxly erect to flaccid, semi-scandent culms and lax panicles bearing few branches tipped by few spikelets. Branching extravaginal. Leaf-sheath membranous, with few, distinct ribs, very sparsely, finely scabrid throughout or only above. Ligule 1.2–8.0 mm long, truncate and erose in lower leaves, tapering in upper leaves, undersides scabrid. Leaf-blade 30–250 × 0.4–2.5 mm, flat, or folded and more or less involute, narrow-linear, undersides almost smooth near base to closely scabrid near acute apex, upper surface ribbed and scabrid on ribs, margins scabrid. Culm 60–800 mm long, weakly erect to flaccid and hanging in surrounding vegetation, more or less geniculate at base, internodes minutely retrorsely scabrid above. Panicle 40–300 × 30–300 mm long, very lax at maturity, usually wider than long, primary branches naked, capillary, finely scabrid, maturing horizontal or reflexed, secondary branches shorter, each tipped by a single spikelet. Spikelets 3–8 mm, light green to purplish. Glumes more or less equal, elliptic-lanceolate, scabrid above on keel and hyaline margin, apex acute or acuminate. Lemma 2.5–3.8 mm, ¾ length of glumes, 5-nerved, elliptic-oblong, truncate, denticulate, lateral nerves usually shortly excurrent, margins and nerves finely scabrid near apex, rarely awn absent. Palea ½ length of lemma or shorter, keels more or less distinct, 0.2 mm apart, apex shallowly bifid. Callus hairs to 1 mm long, to ⅓ length of lemma. Rachilla prolongation 0.1–0.8 mm, bearing a tuft of hairs to 1 mm long; sometimes absent. Lodicules 0.6–0.9 mm, linear, acute. Anthers 0.6–1.2 mm. Seed 1.5–1.8 × 0.5–0.7 mm.