All Species in Polygonum
- Alaska Knotweed (Polygonum humifusum subsp. caurianum)
- Beach Knotweed (Polygonum paronychia)
- Bidwell's Knotweed (Polygonum bidwelliae)
- Bolander's Knotweed (Polygonum bolanderi)
- Box Knotweed (Polygonum buxiforme)
- Broadleaf Knotweed (Polygonum minimum)
- Bushy Knotweed (Polygonum ramosissimum)
- California Knotweed (Polygonum californicum)
- Cascade Knotweed (Polygonum cascadense)
- Coastal Jointweed (Polygonum articulatum)
- Douglas' Knotweed (Polygonum douglasii)
- Erect Knotweed (Polygonum erectum)
- Florida Jointweed (Polygonum basiramia)
- Fowler's Knotweed (Polygonum fowleri)
- Fringed Black Bindweed (Polygonum cilinode)
- Hairy Jointweed (Polygonum delopyrum)
- Hickman's Knotweed (Polygonum hickmanii)
- Largeflower Jointweed (Polygonum nesomii)
- Largeleaf Jointweed (Polygonum smallianum)
- Leathery Knotweed (Polygonum achoreum)
- Marin Knotweed (Polygonum marinense)
- Milkwort Knotweed (Polygonum polygaloides)
- Narrowpoint Knotweed (Polygonum ramosissimum subsp. ramosissimum)
- October Flower (Polygonum polygamum)
- Oddsepal Knotweed (Polygonum heterosepalum)
- Parks' Jointweed (Polygonum parksii)
- Parry's Knotweed (Polygonum parryi)
- Pleatleaf Knotweed (Polygonum tenue)
- Ray's Knotweed (Polygonum raii)
- Sandhill Jointweed (Polygonum fimbriatum)
- Seaside Knotweed (Polygonum glaucum)
- Shasta Knotweed (Polygonum shastense)
- Small's Jointweed (Polygonum dentoceras)
- Southern Jointweed (Polygonum americanum)
- Striped Knotweed (Polygonum striatulum)
- Tall Jointweed (Polygonum tenerum)