3. Saccharum longesetosum (Andersson) V. Narayanaswami in Bor, Fl. Assam. 5: 461. 1940 [“longisetosum”].
长齿蔗茅 chang chi zhe mao
Erianthus longesetosus Andersson, ╓fvers. Kongl. Vetensk.-Akad. Förh. 12: 163. 1855; Eccoilopus hookeri (Hackel) Grassl; E. longesetosus (Andersson) Grassl; Erianthus hookeri Hackel; E. rockii Keng; Saccha-rum hookeri (Hackel) V. Nara-yanaswami; S. longesetosum var. hookeri (Hackel) U. Shukla.
Perennial. Culms 1–3 m tall, 0.5–1 cm in diam., many-noded, glabrous or hairy below panicle. Leaf sheaths longer than internodes, mouth bearded; leaf blades linear-elliptic, 30–50 × 1.5–2(–4) cm, glabrous, abaxial surface glaucous, tapering to base and apex, apex acuminate; ligule 2.3–2.5 mm. Panicle elliptic or oblong in outline, nodding, 15–40 cm, golden brown, branched, axis glabrous or pilose; racemes 3–10 cm; rachis internodes 2.5–4 mm, ciliate with long silky hairs. Spikelets 4–6 mm; callus hairs slightly shorter to longer than spikelet, white or pale yellow; lower glume lanceolate to elliptic-oblong, cartilaginous, golden brown, glossy, thinner and paler near apex, back glabrous or sparsely to densely pilose below middle, upper margins ciliate, apex bidenticulate; lower lemma slightly shorter than glumes; upper lemma linear-oblong, margins ciliate, shortly 2-toothed, awned; awn 1.3–2.8 cm. Anthers 3, 2–3 mm. Fl. and fr. Aug–Oct. 2n = 30.
Grassy hillsides; 300–2700 m. Guangxi, Guizhou, Sichuan, Xizang, Yunnan [Bhutan, N India, Myanmar, Thailand].
This species is variable in spikelet length and hairiness of the panicle. The callus hairs vary from slightly shorter to considerably longer than the spikelet, and the lower glume may be glabrous, thinly hairy, or densely hairy. Sometimes the pedicelled spikelet is hairier than the sessile spikelet. Particularly hairy specimens may be separated as var. hookeri, but there are many intermediate forms. The species as a whole is recognizable by its broad leaf blades glaucous below and evenly tapering to each end, together with a nodding, golden brown panicle of long-awned spikelets.
Neither combination "Erianthus longisetosus [sic] var. hookeri Bor" (Grasses Burma, Ceylon, India, Pakistan, 151. 1960) nor "Saccharum longisetosum [sic] var. hookeri Bor" (loc. cit. 212) was validly published because Bor proposed them simultaneously for the same taxon and based on the same type (alternative names; Saint Louis Code, Art. 34.2).