Polygonum lanatum Roxburgh, Fl. Ind., ed. 1832, 2: 285. 1832; ?P. lanigerum R. Brown var. cristatum Hemsley; Persicaria lanata (Roxburgh) Tzvelev; P. lapathifolia subsp. lanata (Roxburgh) Soják; P. lapathifolia (Linnaeus) S. F. Gray var. lanata (Roxburgh) H. Hara.

Stem and leaf blade densely lanose.

If Polygonum lanigerum var. cristatum (Hemsley, J. Linn. Soc., Bot. 26: 342. 1891) is indeed synonymous with P. lapathifolium var. lanatum (1930), then the correct name at varietal rank under P. lapathifolium would be a new combination based on var. cristatum.

Field margins, along ditches; 200-1100 m. Fujian, Guangdong, Guangxi, Taiwan, Yunnan [Bhutan, India, Indonesia (Java), Malaysia, Myanmar, Nepal, Philippines, Sikkim].