The Genus Persicaria

Water Smartweed, Water Knotweed: Persicaria amphibia (formerly Polygonum amphibium) -

Smartweed, Marshpepper Smartweed: Persicaria hydropiper (formerly Polygonum hydropiper) -

Swamp Smartweed: Persicaria hydropiperoides (formerly Polygonum hydropiperoides) -

Curltop Ladysthumb, Curltop Knotweed, Willow Weed, Dock-leaf Smartweed: Persicaria lapathifolia (formerly Polygonum lapathifolium) -

Spotted Ladysthumb, Spotted Lady's-thumb, Heartweed: Persicaria maculosa (formerly Polygonum persicaria) -

Pinkweed: Persicaria pensylvanica (Polygonum pensylvanicum) -

Water Smartweed, Dotted Smartweed: Persicaria puncatata (formerly Polygonum puncatum) -

Arrowleaf Tearthumb: Persicaria sagittata (formerly Polygonum sagittatum) -

Himalayan Knotweed, Garden Knotweed: Persicaria wallichii (formerly Polygonum polystachyum) -