P. persicaria L., Sp. Pl. 360. 1753; Hook. f., Fl. Brt. Ind. 5: 35.1886; Kom., Fl. USSR 5: 651. 1936; Coode & Cullen in P.H.Davis, Fl. Turk. 2: 273. 1966; Rech. f. & Schiman-Czeika in Rech.f., Fl. Iran. 56: 59. 1968; R. R. Stewart, Ann. Cat. Vasc. Pl. W. Pak. & Kashm. 208. 1972; Bhopal & Chaudhri in Pak. Syst. 1(2): 77. 1977; Persicaria mitis Delarbre, Fl. Auvergne ed. 2: 518. 1800 nom. rejec.; Polygonum biforme Wahelnb., Fl. Suec. 1: 242. 1824; Polygonum maculatum Rafin. in Fl. Ludoviciana 29. 1817; Persicaria vulgaris Webb & Moq. in Webb, Hist. Nat. Canaries 3(2, 3): 219. 1846 (nom. illegit); Polygonum dolichopodum Ohki in Bot. Mag. (Tokyo) 34: 260. 1925; Persicaria dolichopoda (Ohki) Ohki ex Nakai in Rigakhai, 24: 300. 1926; Persicaria maculata (Rafin.) A. Love & D. Love in Acta Hort. Gothob. 20: 164. 1956; non S.F.Gray, l.c. 270; Ronse Decr. & Akeroyd in Bot. J. Linn. Soc. 98: 366. 1988.

Erect, 20-100 cm tall, annual, glabrous, simple-branched herb, rooting at the nodes. Stem brownish-reddish brown, glabrous. Leaves 1.0-14.0 x 0.25-3.5 cm, narrowly lanceolate-elliptic, acuminate, glabrous - pubescent, entire, subsessile, often with a large dark blotch near the middle on the dorsal side, petiole 1-3 mm long. Ochreae 0.4-1.75 cm long, ovate, usually hirsute, ciliate or fimbriate, ciliae 0.2-1.75 cm or more long. Inflorescence 2.0-3.0 (-3.5) cm long, many-flowered, pedunculate raceme; peduncle 1-2 cm long, eglandular. Flowers 1.5-2 mm across, pedicel 1.0-2.0 mm long. Ochreolae broadly ovate, ciliate, ciliae quite long, sometimes short. Tepals 5, dark pink-red, eglandular, biseriate, unequal; obovate, obtuse. Stamens 6, filaments long, unequal. Ovary ovoid, rounded, with 2 styles, style free above, fused below; stigma capitate. Nuts (1.8-) 2-2.25 (-2.5) x c. 1.5 mm, biconvex, black, shining, glabrous, enclosed by the perianth.

Fl. Per.: June-October.

Type: Described from Louisiana.

Very similar to Persicaria lapathifolia but ochreae are ciliate, flowers brightly coloured (pink), the leaves and peduncles eglandular; grows from 1200-4000 m. in damp shady places, among the rocks and marshy places; Distribution: Atlantic region, Central Europe, Mediterranean region, Asia minor, Himalayas - extending up to Japan.