Description from Flora of China
Herbs perennial or less commonly annual, rarely shrubs, rarely dioecious. Roots usually stout (taproots), or sometimes plants rhizomatous. Stems erect, rarely ascending to prostrate, branched, not hollow or sulcate. Leaves simple, often dimorphic, fugacious or persisting, basal and cauline, alternate, margin entire or undulate; ocrea tubular, membranous, margin entire. Inflorescence usually terminal, sometimes terminal and axillary, racemose or paniculate. Pedicel articulate (the functional pedicel consists of the true pedicel and, below the joint, the narrowed united basal parts of the outer tepals (pseudopedicel)). Flowers bisexual or unisexual (unisexual in dioecious, and rarely in polygamo-monoecious plants). Perianth persistent, tepals 6, becoming enlarged and often hardened in fruit; valve (fruiting inner tepal) margin entire, erose, denticulate, or variously dentate, midvein often transformed into tubercles (tuberculate callosities). Stamens 6. Styles 3, elongate; stigmas penicillate. Achenes trigonous, elliptic to ovate.
Rumex s.l. is sometimes subdivided into at least three segregate genera: Rumex s.str., Acetosa Miller, and Acetosella (Meisner) Fourreau, here recognized as subgenera. The generic status of these segregate genera, however, has not been generally accepted by most taxonomists. In some cases intermediate forms exist between them, especially between Acetosa and Acetosella, and they are evidently more closely related to each other than to any outside genus. This favors the retention of Rumex in the traditional broad sense, which is also convenient from the viewpoint of nomenclatural stability.
About 200 species: widely distributed in N and S temperate zones; 27 species (one endemic) in China.
(Authors: Li Anjen (李安仁 Li An-ren); Alisa E. Grabovskaya-Borodina, Sergei L. Mosyakin)