Polygonum lapathifolium L.

Annual, erect or ascending, 20-60 cm tall, annual herb, glabrous or pubescent. Stem simple or branched, often thickened at the nodes, usually with red dots, internodes usually shorter than the leaves. Leaves distinctly petiolate, linear lanceolate, acute to acuminate, (1.5-) 2-10 (-12) x 0.5-2.0 (-2.5) cm, entire, ciliate on margins, midrib and veins, ± tomentose below or glabrous (var. nodosa) sometimes covered with yellow glands. Ochrea 5-20 (-30) mm long, tubular, ovate, ± brownish entire-dentate, eciliate, rarely very finely ciliate at the mouth. Inflorescence many flowered dense, pedunculate, uninterrupted or lax, 1-5 cm long, curved or stiff raceme; peduncle as long as the inflorescence or less, glandular or not. Flowers up to 2.5 mm across, subsessile to pedicellate, pedicel 0.5-1 (-1.5) mm long. Ochreolae 0.5-3 mm long, ovate, acuminate, eciliate, entire to dentate. Tepals 4-5, in two whorls, pink or white or greenish with a reddish tinge, unequal, elliptic-obovate, obtuse, entire. c. 2.0 x 0.75 mm, glandular, glands sessile, yellow. Stamens 5-6 (-8), filaments long, unequal, ovary biconvex, c. 1 mm long, with two styles, styles filiform, free above, fused below, stigmas capitate. Nuts 2-3.5 x 1.5-2.0 mm, biconvex, slightly compressed in the middle, circular to broadly ovate, shining, black-brown. 

 A fairly common and widespread species, grows from plains to 3000 m in moist and shady areas. A highly polymorphic taxon especially in habit, presence or absence of red dots on the stem, colour of the glands on the leaves and perianth, tomentose to almost glabrous leaves, eglandular to glandular peduncle and length and compactness of raceme. The variation in our area in most of the characters is continuous. However, the character of leaf indumentum and length and compactness of raceme seem to be fairly stable. Therefore two varieties are recognized in our region.