cinereus (L.) = ash grey. In reference to the colour of the female bracts.
WCM Protologue Reference:
H.P.Linder, Bothalia 15: 473 (1985)
Vegetative parts: plants tufted, 0.8–4 m tall, basal diameter 0.1–0.3 m, crown diameter 0.1–0.5 m, compact, without spreading rhizomes or stolons or with rhizomes. Rhizome very short with culms aggregated at base, 4–6 mm in diam., culms 1–6 mm apart. Fertile culms unbranched, velvety pubescent, silvery-gray, 0.6–4 m tall, diameter at base 1.5–5 mm, diameter at apex 0.5–2.2 mm. Clusters of sterile branches at the nodes of the fertile branches present. Sterile branches present while flowering. Sheaths closely convoluted (becoming loosely), 40–80 mm long, brown-grey, apical margins broadly chartaceous and soon decaying, hyaline shoulders tall, acute, hyaline shoulder 0.1–0.3 of sheath body length, apex, excluding the membranous lobes, acute. Sheath-mucro penicellate, straight and erect, 10–15 mm long, apical portion of the sheath very quickly decaying, leading to the loss of the awn and the membranous shoulders: these can only be observed on young sheaths. Sterile branch leaf-sheath 3.5–4.5 mm long, hyaline shoulder 4–8 mm long, lacerated, leaf-blade 4.5–10 mm long; leaf blade 0.2–0.3 mm wide. Males: male inflorescence with 21–50 spikelets or 50–100 spikelets, paniculate, 100–350 mm long, 50–100 mm wide. Male inflorescence spathes persistent, upper margins lacerated and largely decayed at anthesis, shorter than spikelets, chartaceous. Male flowers in spikelets. Male spikelets pendulous on flexible pedicels, linear or oblong, apex rounded, 14–35 mm, 5–8 mm, with 24–52 flowers, pedicels shorter than the spikelets or as long as the spikelets or longer than the spikelets, flattened. Male bracts taller than flowers, 7–10 mm long, oblong (triangular), acute, hyaline, bract upper margin like body of bract, bract awn minute or absent, completely silvery. Male flower 3–3.5 mm long. Male tepals sepals more rigid than petals, chartaceous, petals membranous, oblong, inner and outer tepals the same length. Male outer lateral tepals keeled or winged or conduplicate, glabrous. Anthers 1.4–2 mm long, included in the flowers. Pistillode absent. Females: female inflorescence racemose, 100–300 mm long, 30–50 mm wide, with 6–10 spikelets or 11–20 spikelets or 21–50 spikelets. Female spathes longer than the spikelets, not obscuring spikelet, persistent, chartaceous. Female spikelet pedicel simple or pedicel sparsely branching or pedicel much branched, oblong, apex rounded, 20–40 mm long, with 20–48 flowers, with 0 sterile bracts. Female bracts at least twice as long as flowers, 9–20 mm long, oblong or ovate, acute or acuminate, hyaline (usually) or cartilaginous (rarely, then still quite pale), apical margin like rest of bract, same as body of bract, awn minute or absent. Female flower 3.5–5 mm long, without a fleshy pedicel. Female tepals cartilaginous, glabrous and smooth, at least as tall as nut, wrapped around it and obscuring the surface, midrib flush with the tepal body, apices acute, inner and outer whorls the same length or inner whorl shorter than outer. Female outer lateral tepals keeled or winged, wings entire, wider than body, 3.5–5 mm long. Female odd outer tepal oblong, 3.5–4.5 mm long. Female inner tepals oblong, 3.3–4 mm long. Staminodes absent. Styles plumose, white (cream-coloured), 1. Ovary with 1 locule, indehiscent. Fruit: indehiscent fruits with a softer ovary wall. Perianth presence on fruits persistent, winged. Shape of winged dispersal unit oblong, narrower than long. Nut apex smooth, without a distinct cap, wall smooth, (1.76–)2.09(–2.24) mm long, (1.16–)1.41(–1.56) mm diam., shape in side view elliptical or obovate, shape in top view elliptical in cross section, brown (red). Elaiosome absent.