| Polygonum flexuosum Benth., 1839 |
| Polygonum glabrum Cham. & Schltdl., 1828 |
| Polygonum guatemalense Gand., 1919 |
| Polygonum hispidum Kunth, 1818 |
| Polygonum hydropiperoides Michx., 1803 |
| Polygonum hydropiperoides var. hydropiperoides Michx., 1803 |
| Polygonum lapathifolium L., 1753 |
| Polygonum longiocreatum Bartlett, 1907 |
| Polygonum meisnerianum Cham. & Schltdl., 1828 |
| Polygonum meisnerianum var. beyrichianum (Cham. & Schltdl.) Meisn., 1855 |
| Polygonum meisnerianum var. jalapense B.L. Rob., 1900 |
| Polygonum meisnerianum var. meisnerianum Cham. & Schltdl., 1828 |
| Polygonum mexicanum Small, 1892 |
| Polygonum mite Pers., 1805 |
| Polygonum nepalense Meisn., 1826 |
| Polygonum opelousanum Riddell ex Small, 1892 |
| Polygonum paniculatum L., 1759 |
| Polygonum pensylvanicum L., 1753 |
| Polygonum persicaria L., 1753 |
| Polygonum persicarioides Kunth, 1817 |