187. Saccharum Linnaeus, Sp. Pl. 1: 54. 1753.
甘蔗属 gan zhe shu
Authors: Shou-liang Chen & Sylvia M. Phillips
Erianthus Michaux; Narenga Bor; Ripidium Trinius (1820), not Bernhardi (1801).
Perennials, rhizomatous or tufted. Culms robust, up to 7 m tall. Leaf blades cauline, narrowly to broadly linear, midrib usually broad, white; ligule membranous, margin ciliolate. Inflorescence terminal, a large plumose panicle with elongate central axis, its branches bearing numerous hairy racemes; racemes fragile, sessile and pedicelled spikelet of a pair similar, both fertile; rachis internodes and pedicels filiform with cupular apex, pedicels resembling internodes but often shorter. Spikelets usually small, lanceolate, dorsally compressed or pedicelled spikelet more rounded on back; callus short, obtuse, bearded, often with long silky hairs surrounding the spikelet; lower glume membranous, thinly cartilaginous, or becoming leathery below, flat to broadly convex, veins indistinct, laterally 2-keeled; upper glume boat-shaped, resembling lower glume in texture and color; lower floret reduced to an empty hyaline lemma; upper floret bisexual, lemma entire, rarely 2-toothed, sometimes very narrow or small, with or without a short straight awn; stamens 2–3. x = 10.
Between 35 and 40 species: throughout the tropics and subtropics, but mainly in Asia; 12 species (two endemic, two introduced) in China.
Species with awns are sometimes separated as the genus Erianthus, but this is an artificial distinction. Saccharum includes the important crop plant S. officinarum (sugarcane).
The fluffy callus hairs are an efficient aid to wind dispersal.
