Description from
Flora of China
Persicaria attenuata subsp. pulchra (Blume) K. L. Wilson; P. pulchra (Blume) Soják; Polygonum tomentosum Willdenow (1799), not Schrank (1789).
Plants perennial, rhizomatous. Stems erect, sometimes prostrate below, 80-100 cm tall, robust, simple, pilose or glabrescent. Petiole 1-2 cm; leaf blade broadly lanceolate, 10-15 × 1.5-3 cm, both surfaces densely sericeous, base narrowly cuneate, margin entire, ciliate, apex long acuminate; ocrea tubular, 1.5-2 cm, membranous, densely pubescent, apex truncate, cilia 4-6 mm. Inflorescence terminal, of panicled spikes, erect, 3-6 cm; bracts ovate, adpressed hispidulous, each 3- or 4-flowered. Pedicels longer than bracts. Perianth white, 5-parted; tepals elliptic, 3-3.5 mm. Stamens 7 or 8, included. Styles 2, free; stigmas capitate. Achenes included in persistent perianth, black, shiny, orbicular, biconvex, 3-4 mm in diam. Fl. Sep-Oct, fr. Oct-Nov.
In shallow water of swamps, marshy areas; 100-300 m. Guangdong, Guangxi, Taiwan [India, Indonesia, Malaysia, Myanmar, Philippines, Sri Lanka, Thailand; ?Africa, Australia].