Persicaria capitata, the pink-headed persicaria, pinkhead smartweed, pink knotweed, Japanese knotweed, or pink bubble persicaria, is an Asian species of plants in the genus Persicaria within the Polygonaceae (US: buckwheat) family. It is native to Asia (China, South Asia, Indochina) and grown as an ornamental in other countries. It has become naturalized in Australia, South Africa and a few scattered locations in the Americas.Biota of North America Program 2014 county distribution map, Persicaria capitataFlora of North America, Persicaria capitata
Description Persicaria capitata is a prostrate herb. The leaves are 1–6 cm long, 0.7–3 cm wide with pink to red bands or blotches and short scattered hairs. The spikes are 5–10 mm long and 5–7 mm in diameter.Flora of China, Polygonum capitatum Buchanan-Hamilton ex D. Don, 1825. 头花蓼 tou hua liao
Distribution and habitat Persicaria capitata is a native of Asia. It has naturalised in parts of Australia and North America. Between 2008 and 2013 it has been recorded as an invasive plant in Ireland from the Counties Fermanagh, Kilkenny, Wexford and Mayo.Devlin, Z. 2017 A new record for the introduced plant Persicaria capitata (Pink-headed Persicaria), from Newport, Co. Mayo (H27).Irish Naturalists' Journal 35:116
Uses Persicaria capitata has been widely used in China in the treatment of various urologic disorders including urinary calculi and urinary tract infections.Liao SG, Zhang LJ, Sun F, Zhang JJ, Chen AY, Lan YY, Li YJ, Wang AM, He X, Xiong Y, Dong L, Chen XJ, Li YT, Zuo L, Wang YL, "Antibacterial and anti-inflammatory effects of extracts and fractions from Polygonum capitatum." J Ethnopharmacol. 2011 Feb 3; Authors:
See also Reynoutria japonica for another plant species called Japanese knotweed.
References
External links
Jepson Herbarium, University of California