Lachnagrostis leptostachys

Detailed description

Pale green, erect tufted, perennial grass, 150–650 mm tall, with numerous, narrow, involute grey-green to dark green leaves overtopping the lax, delicately branched panicles. Branching intravaginal. Leaf-sheath membranous with few, distinct ribs, smooth or scabrid above, pale green to very light brown. Ligule 2.0–4.5 mm, oblong, very slightly tapered above, truncate, denticulate, undersides ± scabrid, especially near base. Leaf-blade 35–160 × 1–2 mm, mostly involute, 0.5–1.0 mm diameter, undersides sparsely to closely scabrid, upper sides ribbed and closely ciliate-scabrid on ribs; margins finely scabrid, apex acute. Culm 30–180 mm, usually hidden within leaf-sheaths, internodes finely scabrid. Panicle 30–160 × 20–120 mm, purple-red, laxly rachis finely scabrid, branches capillary, finely scabrid, tipped by few spikelets. Spikelets 4.5–6.5 mm, light green to red-green. Glumes ± equal, lanceolate, acute to acuminate, green, red-green, purple, submembranous, sparsely scabrid above, midnerve with sparse prickle-teeth, except near base, margins hyaline, sparsely scabrid near apex. Lemma 2.5–3.0 mm, c. ½ length of glumes, 5-nerved, softly hairy throughout except at apex, elliptic, truncate, lateral nerves shortly excurrent; awn 4–6 mm, straight, or ± curved, ± mid-dorsal, or from upper ⅓ of lemma. Palea c. ½–⅔ length of lemma, elliptic, nerves not evident, margins with 1–2 minute hairs, apex shallowly notched. Callus hairs ± dense below lemma margins, fine, to c. 1 mm, ¼–⅓ length of lemma. Rachilla prolongation to 0.5 mm with fine hair tufts to 1 mm long, or glabrous. Lodicules c.1 mm, narrow-lanceolate, acute. Anthers 0.6–1.2 mm. Seed 1.5 × 0.5 mm.