Description from
Flora of China
Herbs, perennial. Plants hermaphroditic, gynodioecious, polygamo-dioecious, or dioecious, glabrous or variously pubescent, villous or hirsute, hairs 1- to several celled, white or translucent. Rhizomes elongate, with fibrous roots, or rhizomes reduced, with fascicled, often clavate, roots. Taproots absent (Chinese spp.). Stolons present or absent. Basal leaves rosulate, petiolate or spatulate, undivided, pinnate or pinnatifid, persistent or caducous. Cauline leaves opposite, petiolate to sessile; petiole length typically diminishing upward along stem; blade pinnate, pinnatifid, pinnatisect, or undivided. Inflorescence paniculiform or corymbiform, at anthesis: flowers in remote terminal clusters or in a densely capitate head, branches elongating in fruit; lowermost bracts often lobed, bracts otherwise simple and entire; bracteoles simple, similar to bracts; flowers bisexual, male (not in China?) or female. Calyx a ring at anthesis, unfurling into 5-15 white, plumose segments, 4-8 mm, in mature fruit. Corolla funnelform, rotate or salverform; tube usually gibbous near base; limb 5-lobed. Stamens 3 (4 in Valeriana kawakamii), inserted on corolla tube. Achene compressed dorsally, 3-veined on abaxial side, 1-veined on adaxial side, sterile locules reduced; crowned by persistent, plumose calyx, segments 2-7 mm.
A difficulty in the key is the rhizomes as unfortunately many collections do not have the rhizomes attached.
About 300 species: Asia, Europe, North and South America; 21 species (13 endemic) in China.