Persicaria hydropiper

Water pepper
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Order:	Caryophyllales
Family:	Polygonaceae
Genus:	Persicaria
Species:	P. hydropiper
Binomial name
	Persicaria hydropiper; (L.) Delabre 1800
Synonyms
	Synonymy Polygonum hydropiper L. 1753 ; Persicaria hydropiper (L.) Opiz 1852 ; Persicaria hydropiper (L.) Spach 1841 ; Persicaria acris Gilib. ; Persicaria glandulosa Nakai & Ohki ; Persicaria urens Garsault ; Persicaria vernalis Nakai ; Peutalis hydropiper Raf. ; Polygonum glandulosum Poir. ; Polygonum gracile Salisb. ; Polygonum hecasanthum Schur ; Polygonum hidropiper Neck. ; Polygonum oleraceum Schur ; Polygonum schinzii J. Schust. ;

Persicaria hydropiper (syn. Polygonum hydropiper), also known as water pepper, marshpepper knotweed, arse smart or tade, is a plant of the family Polygonaceae. A widespread species, Persicaria hydropiper is found in Australia, New Zealand, temperate Asia, Europe and North America. The plant grows in damp places and shallow water. Cultivated varieties are eaten in East Asia for their pungent flavor.