Description from Flora of China
Herbs perennial, usually andropolygamous, with short, thick rhizomes and stout, slightly fleshy roots. Stems erect, terete, stout, usually pubescent, leafy, usually enclosed basally by fibers or reticulate fibers formed from disintegrated sheaths. Leaves alternate, sheathed and clasping, broad to narrow, strongly plicately veined, basally usually narrowed. Inflorescence usually a terminal panicle, many flowered. Flowers shortly pedicellate or subsessile, white, yellowish, green, or dark purple-brown, funnelform, cupular to opening flat. Tepals 6, usually free, spreading, persistent in fruit. Stamens 6, inserted at base of tepals; anthers reniform to cordate-orbicular, with locules confluent and dehiscent by an apical valve. Ovary 3-loculed, slightly 3-lobed apically, ovules usually many. Styles 3, short, persistent, stigmatic adaxially. Fruit a septicidal capsule. Seeds several per valve, flattened, narrowly winged.
About 40 species: mainly in temperate regions of the N hemisphere; 13 species (eight endemic) in China.
(Authors: Chen Xinqi (陈心启 Chen Sing-chi); Hiroshi Takahashi)