Alpine Knotweed, Newberry's Knotweed, Fleeceflower, Alpine Knotweed, Davis' Knotweed: Aconogonon davisiae var. davisiae (Synonyms: Polygonum davisiae, Polygonum newberryi, Polygonum newberryi var. newberryi) -
Alpine Knotweed, Jimson Knotweed, Pokeweed Fleeceflower, Poke Knotweed: Aconogonon phytolaccifolium var. phytolaccifolium (Synonym: Polygonum phytolaccifolium) -
American Bistort, Snakeweed, Mountain Meadow Knotweed, Western Bistort: Bistorta bistortoides (Synonyms: Persicaria bistortoides, Polygonum bistortoides, Polygonum bistortoides var. linearifolium, Polygonum bistortoides var. oblongifolium, Polygonum cephalophorum, Polygonum glastifolium, Polygonum vulcanicum) -
Black Bindweed, Climbing Bindweed, Ivy Bindweed, Wild Buckwheat: Fallopia convolvulus (Synonyms: Bilderdykia convolvulus, Fallopia convolvulus var. subulata, Polygonum convolvulus, Polygonum convolvulus var. convolvulus, Reynoutria convolvulus, Tinaria convolvulus) -
Pink Knotweed, Water Smartweed: Persicaria amphibia (Synonyms: Polygonum amphibium, Polygonum amphibium var. coccineum, Polygonum amphibium var. emersum, Polygonum amphibium var. natans, Polygonum amphibium var. stipulaceum, Polygonum coccineum, Polygonum coccineum var. coccineum, Polygonum coccineum var. hartwrightii, Polygonum natans, Polygonum natans var. hartwrightii) -
Yard Buckwheat, Prostrate Knotweed, Doorweed: Polygonum aviculare -
Douglas' Knotweed, Austin's Knotweed: Polygonum douglasii (Synonyms: Polygonum douglasii ssp. douglasii, Polygonum douglasii var. douglasii, Polygonum douglasii var. latifolium, Polygonum montanum) -
Curltop Ladysthumb, Dock-leaf Smartweed, Pale Smartweed, Willow Weed: Polygonum lapathifolium var. lapathifolium (Synonyms: Polygonum incarnatum, Polygonum lapathifolium, Polygonum lapathifolium var. salicifolium, Polygoum linicola, Polygonum nodosum, Polygonum scabrum, Polygonum tomentosum) -
Broadleaf Knotweed, Broad-leaved Knotweed, Leafy Dwarf Knotweed, Redstem Knotweed, Zigzag Knotweed: Polygonum minimum (Synonym: Polygonum torreyi) -
Closeflowered Knotweed: Polygonum polygaloides ssp. confertiflorum (Synonyms: Polygonum confertiflorum, Polygonum imbricatum, Polygonum kelloggii var. confertiflorum, Polygonum watsonii) -
Kellogg's Knotweed: Polygonum polygaloides ssp. kellogii (Synonyms: Polygonum kelloggii, Polygonum minutissimum, Polygonum unifolium) -
Sawatch Knotweed: Polygonum sawatchense ssp. sawatchense -