Setaria pumila (Poir.) Roem. & Schult.

Loosely to densely tufted, erect annuals, 25–35–(85) cm, green or yellow-green, often purplish near base. Leaf-sheath strongly compressed, firm, but ± membranous towards margins, glabrous, flattened and keeled. Ligule ciliate, hairs 0.5–1.5 mm. Leaf-blade (3)–5–15–(23) cm × (2.5)–3–5–(6) mm, flat, soft, linear or linear-lanceolate, distinctly twisted, tapering above, glabrous, or adaxially slightly scabrid and with long, fine, soft, tubercle-based hairs towards base; margins very minutely scabrid, tip slender, acuminate. Culm 15–65–(75) cm, compressed, erect or geniculate-ascending, rooting at lower nodes, internodes scabrid, to ± densely minutely pubescent below panicle. Panicle (1)–2.5–10 cm × 5–15 mm, cylindric, dense-flowered; rachis densely pubescent, with numerous, very short, close-set, pubescent branches, each usually bearing a single spikelet, sometimes with 1–2 abortive spikelets, subtended by 5–10 greenish to golden brown, antrorsely scabrid, unequal bristles (5–8.5 mm). Spikelets 2.5–3.5 mm, pale green at first, later purple, falling entire at maturity. Lower glume 0.8–1.7 mm, ovate, acute or apiculate, 3-nerved, upper 1.7–2.3 mm, subacute, 5-nerved, ovate-orbicular, convex. Lower floret usually Ø, rarely ♂: lemma 5-nerved, acute; palea ≈ lemma, hyaline; anthers 0.9–1.4 mm, or 0. Upper floret ☿: lemma = spikelet, crustaceous, prominently transversely rugose, becoming yellowish or brownish, broadly naviculate, very convex, sometimes apiculate; palea of same texture but ≤ lemma, keels rounded and thickened, minutely hairy towards apex, otherwise glabrous; anthers 0.9–1.6 mm; caryopsis c. 1.5–2 mm.

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