| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| POLI8 | Polygonum littorale Link | Polygonum buxiforme | Polygonaceae
|
| POLO12 | Polygonum longisetum de Bruyn | Polygonum caespitosum var. longisetum | Polygonaceae
|
| POLOO | Polygonum longistylum Small var. omissum (Greene) Stanford | Polygonum pensylvanicum | Polygonaceae
|
| POLO13 | Polygonum longistylum Small | Polygonum pensylvanicum | Polygonaceae
|
| POMA28 | Polygonum macounii Small ex Macoun | Polygonum viviparum | Polygonaceae
|
| POMA9 | Polygonum majus (Meisn.) Piper | Polygonum douglasii ssp. majus | Polygonaceae
|
| POMA15 | Polygonum marinense Mert. & Raven | Marin knotweed | Polygonaceae
|
| POMA27 | Polygonum maritimum auct. non L. | Polygonum glaucum | Polygonaceae
|
| POMEB | Polygonum meisnerianum Cham. & Schlecht. var. beyrichianum (Cham. & Schlecht.) Meisn. | branched tearthumb | Polygonaceae
|
| POME4 | Polygonum meisnerianum Cham. & Schlecht. | branched tearthumb | Polygonaceae
|
| POME6 | Polygonum mexicanum auct. non Small | Polygonum pensylvanicum | Polygonaceae
|
| POMI14 | Polygonum microspermum (Engelm.) Small | Polygonum douglasii ssp. engelmannii | Polygonaceae
|
| POMI2 | Polygonum minimum S. Wats. | broadleaf knotweed | Polygonaceae
|
| POMIS | Polygonum minus Huds. var. subcontinuum (Meisn.) Fern. | Polygonum persicaria | Polygonaceae
|
| POMI11 | Polygonum minus auct. non Huds. | Polygonum persicaria | Polygonaceae
|
| POMII | Polygonum mississippiense Stanford var. interius Stanford | Polygonum pensylvanicum | Polygonaceae
|
| POMI10 | Polygonum mississippiense Stanford | Polygonum pensylvanicum | Polygonaceae
|
| POMO8 | Polygonum monspeliense Pers. | Polygonum aviculare | Polygonaceae
|
| POMO16 | Polygonum montanum Small | Polygonum douglasii ssp. douglasii | Polygonaceae
|
| POMO4 | Polygonum montereyense Brenckle | Polygonum arenastrum | Polygonaceae
|
| POMUT | Polygonum muehlenbergii S. Wats. var. terrestre (Willd.) Trel. | Polygonum amphibium var. emersum | Polygonaceae
|
| POMU10 | Polygonum muehlenbergii S. Wats. | Polygonum amphibium var. emersum | Polygonaceae
|
| PONA3 | Polygonum natans Eat. | Polygonum amphibium var. stipulaceum | Polygonaceae
|
| PONE8 | Polygonum neglectum Bess. | Polygonum bellardii | Polygonaceae
|
| PONE9 | Polygonum nepalense Meisn. | Nepalese smartweed | Polygonaceae
|
| PONEG | Polygonum newberryi Small var. glabrum G.N. Jones | Polygonum davisiae | Polygonaceae
|
| PONE5 | Polygonum newberryi Small | Polygonum davisiae | Polygonaceae
|
| PONO5 | Polygonum nodosum Pers. | Polygonum lapathifolium | Polygonaceae
|
| PONU3 | Polygonum nuttallii Small | Polygonum douglasii ssp. nuttallii | Polygonaceae
|
| POON | Polygonum oneillii Brenckle | Polygonum lapathifolium | Polygonaceae
|
| POOPA | Polygonum opelousanum Riddell ex Small var. adenocalyx Stanford | Polygonum hydropiperoides | Polygonaceae
|
| POOP2 | Polygonum opelousanum Riddell ex Small | Polygonum hydropiperoides | Polygonaceae
|
| POOR2 | Polygonum orientale L. | kiss me over the garden gate | Polygonaceae
|
| POOXR | Polygonum oxyspermum C.A. Mey. & Bunge ex Ledeb. ssp. raii (Bab.) Webb & Chater | Polygonum raii | Polygonaceae
|
| POPA7 | Polygonum paronychia Cham. & Schlecht. | beach knotweed | Polygonaceae
|
| POPA33 | Polygonum paronychioides Small ex Rydb. | knotweed | Polygonaceae
|
| POPA8 | Polygonum parryi Greene | Parry's knotweed | Polygonaceae
|
| POPA9 | Polygonum patulum Bieb. | Bellard's smartweed | Polygonaceae
|
| POPEO2 | Polygonum pensylvanicum L. ssp. oneillii (Brenckle) Hult�n | Polygonum lapathifolium | Polygonaceae
|
| POPED | Polygonum pensylvanicum L. var. durum Stanford | Polygonum pensylvanicum | Polygonaceae
|
| POPEE | Polygonum pensylvanicum L. var. eglandulosum J.C. Myers | Polygonum pensylvanicum | Polygonaceae
|
| POPEG | Polygonum pensylvanicum L. var. genuinum Fern. | Polygonum pensylvanicum | Polygonaceae
|
| POPEL2 | Polygonum pensylvanicum L. var. laevigatum Fern. | Polygonum pensylvanicum | Polygonaceae
|
| POPER3 | Polygonum pensylvanicum L. var. rosiflorum J.B.S. Norton | Polygonum pensylvanicum | Polygonaceae
|
| POPE2 | Polygonum pensylvanicum L. | Pennsylvania smartweed | Polygonaceae
|
| POPE10 | Polygonum perfoliatum L. | Asiatic tearthumb | Polygonaceae
|
| POPEA2 | Polygonum persicaria L. var. angustifolium Beckh. | Polygonum persicaria | Polygonaceae
|
| POPER2 | Polygonum persicaria L. var. ruderale (Salisb.) Meisn. | Polygonum persicaria | Polygonaceae
|
| POPE3 | Polygonum persicaria L. | spotted ladysthumb | Polygonaceae
|
| POPE20 | Polygonum persicarioides Kunth | Polygonum hydropiperoides | Polygonaceae
|
| POPH | Polygonum phytolaccifolium Meisn. ex Small | poke knotweed | Polygonaceae
|
| POPL9 | Polygonum plebeium R. Br. | | Polygonaceae
|
| POPL4 | Polygonum plumosum Small | Polygonum bistorta var. plumosum | Polygonaceae
|
| POPO3 | Polygonum polycnemoides Jaubert & Spach | manyleg knotweed | Polygonaceae
|
| POPOC | Polygonum polygaloides Wallich ex Meisn. ssp. confertiflorum (Nutt. ex Piper) Hickman | fruitleaf knotweed | Polygonaceae
|
| POPOE | Polygonum polygaloides Wallich ex Meisn. ssp. esotericum (L.C. Wheeler) Hickman | whitemargin knotweed | Polygonaceae
|
| POPOK | Polygonum polygaloides Wallich ex Meisn. ssp. kelloggii (Greene) Hickman | Kellogg's knotweed | Polygonaceae
|
| POPOP3 | Polygonum polygaloides Wallich ex Meisn. ssp. polygaloides | milkwort knotweed | Polygonaceae
|
| POPO4 | Polygonum polygaloides Wallich ex Meisn. | milkwort knotweed | Polygonaceae
|
| POPO18 | Polygonum polygamum Vent. | Polygonella polygama | Polygonaceae
|
| POPO5 | Polygonum polystachyum Wallich ex Meisn. | cultivated knotweed | Polygonaceae
|
| POPO16 | Polygonum portoricense Bertero ex Small | Polygonum densiflorum | Polygonaceae
|
| POPR10 | Polygonum prolificum (Small) B.L. Robins. | Polygonum ramosissimum var. prolificum | Polygonaceae
|
| POPR9 | Polygonum provinciale K. Koch | Polygonum bellardii | Polygonaceae
|
| POPUA | Polygonum punctatum Ell. var. aquatile (Mart.) Fern. | Polygonum punctatum var. punctatum | Polygonaceae
|
| POPUC2 | Polygonum punctatum Ell. var. confertiflorum (Meisn.) Fassett | dotted smartweed | Polygonaceae
|
| POPUE | Polygonum punctatum Ell. var. ellipticum Fassett | Polygonum punctatum var. punctatum | Polygonaceae
|
| POPUL2 | Polygonum punctatum Ell. var. leptostachyum (Meisn.) Small | Polygonum punctatum var. confertiflorum | Polygonaceae
|
| POPUM | Polygonum punctatum Ell. var. majus (Meisn.) Fassett | Polygonum robustius | Polygonaceae
|
| POPUP | Polygonum punctatum Ell. var. parviflorum Fassett | Polygonum punctatum var. punctatum | Polygonaceae
|
| POPUP7 | Polygonum punctatum Ell. var. parvum Victorin & Rouss. | Polygonum punctatum var. confertiflorum | Polygonaceae
|
| POPUP4 | Polygonum punctatum Ell. var. punctatum | dotted smartweed | Polygonaceae
|
| POPUR | Polygonum punctatum Ell. var. robustius Small | Polygonum robustius | Polygonaceae
|
| POPU5 | Polygonum punctatum Ell. | dotted smartweed | Polygonaceae
|
| POPU11 | Polygonum puritanorum Fern. | Polygonum persicaria | Polygonaceae
|
| PORA6 | Polygonum raii Bab. | Ray's knotweed | Polygonaceae
|
| PORAP | Polygonum ramosissimum Michx. var. prolificum Small | bushy knotweed | Polygonaceae
|
| PORAR | Polygonum ramosissimum Michx. var. ramosissimum | bushy knotweed | Polygonaceae
|
| PORA3 | Polygonum ramosissimum Michx. | bushy knotweed | Polygonaceae
|
| PORO | Polygonum robustius (Small) Fern. | stout smartweed | Polygonaceae
|
| PORU12 | Polygonum rurivagum Jord. ex Boreau | Polygonum bellardii | Polygonaceae
|
| POSA4 | Polygonum sachalinense F. Schmidt ex Maxim. | giant knotweed | Polygonaceae
|
| POSAG | Polygonum sagittatum L. var. gracilentum Fern. | Polygonum sagittatum | Polygonaceae
|
| POSA5 | Polygonum sagittatum L. | arrowleaf tearthumb | Polygonaceae
|
| POSA23 | Polygonum salicifolium Brouss. ex Willd. | knotweed | Polygonaceae
|
| POSA17 | Polygonum sawatchense Small | Polygonum douglasii ssp. johnstonii | Polygonaceae
|
| POSC15 | Polygonum scabrum Moench | Polygonum lapathifolium | Polygonaceae
|
| POSCC | Polygonum scandens L. var. cristatum (Engelm. & Gray) Gleason | climbing false buckwheat | Polygonaceae
|
| POSCD | Polygonum scandens L. var. dumetorum (L.) Gleason | climbing false buckwheat | Polygonaceae
|
| POSCS | Polygonum scandens L. var. scandens | climbing false buckwheat | Polygonaceae
|
| POSC3 | Polygonum scandens L. | climbing false buckwheat | Polygonaceae
|
| POSE4 | Polygonum segetum Kunth | field smartweed | Polygonaceae
|
| POSEI | Polygonum setaceum Baldw. var. interjectum Fern. | Polygonum setaceum | Polygonaceae
|
| POSET | Polygonum setaceum Baldw. var. tonsum Fern. | Polygonum setaceum | Polygonaceae
|
| POSE6 | Polygonum setaceum Baldw. | bog smartweed | Polygonaceae
|
| POSH | Polygonum shastense Brewer ex Gray | Shasta knotweed | Polygonaceae
|
| POSP10 | Polygonum spaethii Dammer | Polygonum orientale | Polygonaceae
|
| POSP | Polygonum spergulariiforme Meisn. ex Small | Polygonum douglasii ssp. spergulariiforme | Polygonaceae
|
| POST7 | Polygonum striatulum B.L. Robins. | striped knotweed | Polygonaceae
|
| POTA3 | Polygonum tataricum L. | Fagopyrum tataricum | Polygonaceae
|
| POTEM | Polygonum tenue Michx. var. microspermum Engelm. | Polygonum douglasii ssp. engelmannii | Polygonaceae
|