Trisetum lasiorhachis (Hack.) Edgar

Strong, dense but narrow tufts, (5)–12–60–(85) cm, sometimes rhizomatous, with pale straw-coloured leaf-sheaths and dull green to grey-green leaf-blades usually with scattered long hairs, with pilose culms and often pubescent panicle-rachis and branches; branching extravaginal. Leaf-sheath to 6 cm, pubescent. Collar hairs few, very long, fine. Ligule 0.3–0.5–(0.8) mm, truncate, erose, glabrous or ciliate. Leaf-blade 5–25 cm × 1.3–3 mm, flat, rarely inrolled and narrower, often with scattered long hairs, abaxially prickle-toothed towards tip, adaxially ribbed with ± scattered minute prickle-teeth or short hairs on ribs; margins minutely prickle-toothed, and often with scattered long hairs. Culm 10–50 cm, internodes pilose above and below nodes, densely pilose, pubescent, or sometimes glabrous towards panicle. Panicle (3)–7–14–(21) × 1–3–(5) cm, lanceolate, somewhat open with visible rachis but spikelets clustered and individually inconspicuous; rachis, branches, and pedicels densely pilose to sparsely, minutely hairy. Spikelets 5–8 mm, pale green, often purple-tinged. Glumes unequal, keels often strong, prickle-toothed in upper ½ or almost throughout; lower ⅔-⅘ length of upper, narrow-oblong, tapered to often long-acuminate tip, upper < spikelet, elliptic, acute to shortly acuminate; margins almost entire with very few prickle-teeth near tip. Lemma 5–7.5 mm, bicuspid, minutely prickle-toothed or papillate throughout; awn 5–9.5 mm, straight to later recurved, insertion in upper ½ to upper ⅓ of lemma. Palea minutely prickle-toothed on keels and rarely on margins. Callus hairs to 0.8 mm. Rachilla hairs to 2 mm. Lodicules c. 1.3 mm, glabrous. Anthers 1.8–2.2 mm. Gynoecium: ovary to 1 mm; stigma-styles to 2.4 mm. Caryopsis c. 2.5 × 0.8 mm.

[From: Edgar and Connor (2000) Flora of New Zealand. Volume 5 (second printing).]