Cenchrus purpurascens Thunb.

Coarse grey-green tussocks of medium size, with narrow wiry leaves; branching intravaginal. Leaf-sheath hard, strongly keeled, glabrous, shining, brownish or often pinkish, margins membranous. Ligule 0.3–0.6 mm, a densely, shortly ciliate rim. Leaf-blade 15–30 cm × 1–1.5 mm diam., folded or involute, sometimes flat, linear, long-tapering, abaxially glabrous, adaxially often shallowly ribbed, ribs minutely scabrid, occasionally with a few soft hairs near ligule; margins minutely scabrid, tip acuminate. Culm 20–40 cm, erect, rounded or ± compressed, internodes loosely covered by fine, long, soft hairs near panicle. Panicle 7–12 cm, spike-like, cylindric, purplish; rachis and ± appressed branches and pedicels soft-hairy. Spikelets 5.5–6.5 mm, shortly pedicelled, densely clustered on rachis, narrow-lanceolate, acute, light creamy brown, minutely scabrid, greenish below, deep purple-brown towards apex, usually solitary within a much longer involucre of numerous, fine, erect, short-scabrid unequal bristles (15–25 mm), united at base; rarely 2 spikelets within involucre. Glumes « spikelet, unequal, submembranous; lower 0.5–1 mm, varying from nerveless, ± cuneate or rimlike, to longer-lanceolate, 1-nerved, upper 2–3 mm, c. ⅓ length of spikelet, faintly 5–(7)-nerved. Lower floret Ø: lemma 5–6 mm, ≈ spikelet, submembranous, 7-nerved, almost enclosing lemma of upper floret; palea 0. Upper floret ☿: lemma 5.5–6.5 mm, somewhat chartaceous, 5–7-nerved, ± enclosing palea; palea similar to lemma but slightly shorter, slightly rounded, nerves 2, glabrous; lodicules 0.2–0.5 mm; anthers 2.7–3.5 mm; styles connate below feathery stigmas, or sometimes partly or wholly free; caryopsis c. 2–2.5 × 1 mm, dark brownish.

[From: Edgar and Connor (2000) Flora of New Zealand. Volume 5 as Pennisetum alopecuroides (L.) Spreng.]