| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| POTE2 | Polygonum tenue Michx. | pleatleaf knotweed | Polygonaceae
|
| POTE6 | Polygonum texense M.C. Johnston | Polygonum striatulum | Polygonaceae
|
| POTO3 | Polygonum tomentosum Schrank | Polygonum lapathifolium | Polygonaceae
|
| POTR16 | Polygonum triandrum Coolidge | Polygonum douglasii ssp. johnstonii | Polygonaceae
|
| POTR17 | Polygonum triangulum Bickn. | Polygonum ramosissimum var. ramosissimum | Polygonaceae
|
| POUN5 | Polygonum unifolium Greene | Polygonum polygaloides ssp. kelloggii | Polygonaceae
|
| POUT | Polygonum utahense Brenckle & Cottam | Polygonum douglasii ssp. johnstonii | Polygonaceae
|
| POUV3 | Polygonum uvifera L. | Coccoloba uvifera | Polygonaceae
|
| POVIG2 | Polygonum virginianum L. var. glaberrimum (Fern.) Steyermark | Polygonum virginianum | Polygonaceae
|
| POVI2 | Polygonum virginianum L. | jumpseed | Polygonaceae
|
| POVIA | Polygonum viviparum L. var. alpinum Wahlenb. | Polygonum viviparum | Polygonaceae
|
| POVIM2 | Polygonum viviparum L. var. macounii (Small ex Macoun) Hult�n | Polygonum viviparum | Polygonaceae
|
| POVI3 | Polygonum viviparum L. | alpine bistort | Polygonaceae
|
| POVU4 | Polygonum vulcanicum Greene | Polygonum bistortoides | Polygonaceae
|
| POWA3 | Polygonum watsonii Small | Polygonum polygaloides ssp. confertiflorum | Polygonaceae
|
| POZU | Polygonum zuccarinii Small | Polygonum cuspidatum | Polygonaceae
|
| POLYG4 | Polygonum L. | knotweed | Polygonaceae
|
| POAL16 | Polymeridium albidum (Mull. Arg.) R. C. Harris | | Trypetheliaceae
|
| POAL27 | Polymeridium albocinereum (Krempelh.) R. C. Harris | | Trypetheliaceae
|
| POCA38 | Polymeridium catapastum (Nyl.) R. C. Harris | | Trypetheliaceae
|
| POCO31 | Polymeridium contendens (Nyl.) R. C. Harris | | Trypetheliaceae
|
| POPL6 | Polymeridium pleiomerellum (Mull. Arg.) R. C. Harris | Polymeridium albocinereum | Trypetheliaceae
|
| POPR18 | Polymeridium proponens (Nyl.) R. C. Harris | | Trypetheliaceae
|
| POQU3 | Polymeridium quinqueseptatum (Nyl.) R. C. Harris | | Trypetheliaceae
|
| POSU13 | Polymeridium subcinereum (Nyl.) R. C. Harris | | Trypetheliaceae
|
| POLYM2 | Polymeridium (Mull. Arg.) R. C. Harris | polymeridium | Trypetheliaceae
|
| POCAR | Polymnia canadensis L. var. radiata Gray | Polymnia canadensis | Asteraceae
|
| POCA11 | Polymnia canadensis L. | whiteflower leafcup | Asteraceae
|
| POCO25 | Polymnia cossatotensis A.B. Pittman & V. Bates | Cossatot Mountain leafcup | Asteraceae
|
| POLA8 | Polymnia laevigata Beadle | Tennessee leafcup | Asteraceae
|
| PORA9 | Polymnia radiata (Gray) Small | Polymnia canadensis | Asteraceae
|
| POSO4 | Polymnia sonchifolia Poeppig & Endl. | yacon | Asteraceae
|
| POUVD | Polymnia uvedalia (L.) L. var. densipilis Blake | Smallanthus uvedalius | Asteraceae
|
| POUVF | Polymnia uvedalia (L.) L. var. floridana Blake | Smallanthus uvedalius | Asteraceae
|
| POUV2 | Polymnia uvedalia (L.) L. | Smallanthus uvedalius | Asteraceae
|
| POLYM | Polymnia L. | polymnia | Asteraceae
|
| POAN12 | Polyotus angustifolius Nutt. | Asclepias stenophylla | Asclepiadaceae
|
| POSE13 | Polypappus sericeus Nutt. | Pluchea sericea | Asteraceae
|
| POAB5 | Polypodium abruptum Desv. | Thelypteris abrupta | Thelypteridaceae
|
| POAM7 | Polypodium amorphum Suksdorf | irregular polypody | Polypodiaceae
|
| POAN11 | Polypodium anfractuosum Kunze ex Klotzsch | Melpomense anfractuosa | Grammitidaceae
|
| POAN13 | Polypodium angustifolium Sw. | Campyloneurum angustifolium | Polypodiaceae
|
| POAP | Polypodium appalachianum Haufler & Windham | Appalachian polypody | Polypodiaceae
|
| POAS2 | Polypodium aspleniifolium L. | Grammitis aspleniifolia | Grammitidaceae
|
| POAS3 | Polypodium astrolepis Liebm. | Pleopeltis astrolepis | Polypodiaceae
|
| POAT2 | Polypodium attenuatum Humb. & Bonpl. ex Willd. | tapered polypody | Polypodiaceae
|
| POAUA | Polypodium aureum L. var. areolatum (Humb. & Bonpl. ex Willd.) Baker | Phlebodium pseudoaureum | Polypodiaceae
|
| POAU6 | Polypodium aureum L. | Phlebodium aureum | Polypodiaceae
|
| POCAK | Polypodium californicum Kaulfuss var. kaulfussii D.C. Eat. | Polypodium californicum | Polypodiaceae
|
| POCA12 | Polypodium californicum Kaulfuss | California polypody | Polypodiaceae
|
| POCA26 | Polypodium calirhiza S. Whitmore & A.R. Sm. | nested polypody | Polypodiaceae
|
| POCAA3 | Polypodium camptophyllarium F�e var. abbreviatum A.M. Evans | Pecluma camptophyllaria ssp. abbreviata | Polypodiaceae
|
| POCH7 | Polypodium chnoodes Spreng. | Polypodium dissimile | Polypodiaceae
|
| POCO23 | Polypodium consimile Mett. | Pecluma consimilis | Polypodiaceae
|
| POCO22 | Polypodium costatum Kunze | Campyloneurum costatum | Polypodiaceae
|
| POCR10 | Polypodium crassifolium L. | Niphidium crassifolium | Polypodiaceae
|
| POCU11 | Polypodium cultratum Willd. | Grammitis cultrata | Grammitidaceae
|
| PODE8 | Polypodium decumanum Willd. | Phlebodium decumanum | Polypodiaceae
|
| PODI3 | Polypodium dispersum A.M. Evans | Pecluma dispersa | Polypodiaceae
|
| PODI4 | Polypodium dissimile L. | forkvein polypody | Polypodiaceae
|
| PODU6 | Polypodium duale Maxon | Cochlidium serrulatum | Grammitidaceae
|
| PODU7 | Polypodium dulce Poir. | treetrunk polypody | Polypodiaceae
|
| POER5 | Polypodium erythrolepis Weatherby | Pleopeltis polylepis var. erythrolepis | Polypodiaceae
|
| POGL8 | Polypodium glycyrrhiza D.C. Eat. | licorice fern | Polypodiaceae
|
| POHA14 | Polypodium haalilioanum Brack. | Adenophorus haalilioanus | Grammitidaceae
|
| POHE3 | Polypodium hesperium Maxon | western polypody | Polypodiaceae
|
| POHE9 | Polypodium hessii Maxon | Grammitis hessii | Grammitidaceae
|
| POHE10 | Polypodium heterophyllum L. | Microgramma heterophylla | Polypodiaceae
|
| POHO7 | Polypodium hookeri Brack. | Grammitis hookeri | Grammitidaceae
|
| POHY5 | Polypodium hymenophylloides Kaulfuss | Adenophorus hymenophylloides | Grammitidaceae
|
| POJU6 | Polypodium jubiforme Kaulfuss | Lellingeria suspensa | Grammitidaceae
|
| POKN | Polypodium knudsenii Hieron. | Polypodium pellucidum var. pellucidum | Polypodiaceae
|
| POLA9 | Polypodium lanceolatum L. | lanceleaf polypody | Polypodiaceae
|
| POLA11 | Polypodium latum (T. Moore) T. Moore ex Sodiro | Campyloneurum latum | Polypodiaceae
|
| POLI11 | Polypodium limbospermum auct. non All. | Thelypteris quelpaertensis | Thelypteridaceae
|
| POLI9 | Polypodium lineare Thunb. | Lepisorus thunbergianus | Polypodiaceae
|
| POLO5 | Polypodium loriceum L. | clambering polypody | Polypodiaceae
|
| POLY | Polypodium lycopodioides L. | Microgramma lycopodioides | Polypodiaceae
|
| POMO11 | Polypodium mollissimum F�e | Grammitis mollissima | Grammitidaceae
|
| POMO10 | Polypodium montense F.A. Lang | Polypodium amorphum | Polypodiaceae
|
| POMY4 | Polypodium myosuroides Sw. | Lellingeria myosuroides | Grammitidaceae
|
| PONO6 | Polypodium noveboracense L. | Thelypteris noveboracensis | Thelypteridaceae
|
| POPE9 | Polypodium pectinatum L. | Pecluma pectinata | Polypodiaceae
|
| POPEP2 | Polypodium pellucidum Kaulfuss var. pellucidum | dotted polypody | Polypodiaceae
|
| POPEV | Polypodium pellucidum Kaulfuss var. vulcanicum Skottsberg | dotted polypody | Polypodiaceae
|
| POPE5 | Polypodium pellucidum Kaulfuss | dotted polypody | Polypodiaceae
|
| POPHL | Polypodium phyllitidis L. var. latum (T. Moore) Proctor | Campyloneurum latum | Polypodiaceae
|
| POPH4 | Polypodium phyllitidis L. | Campyloneurum phyllitidis | Polypodiaceae
|
| POPH5 | Polypodium phymatodes L. | Microsorum scolopendria | Polypodiaceae
|
| POPI5 | Polypodium piloselloides L. | Microgramma piloselloides | Polypodiaceae
|
| POPL2 | Polypodium plumula Humb. & Bonpl. ex Willd. | Pecluma plumula | Polypodiaceae
|
| POPOM | Polypodium polypodioides (L.) Watt var. michauxianum Weatherby | Pleopeltis polypodioides ssp. michauxiana | Polypodiaceae
|
| POPO6 | Polypodium polypodioides (L.) Watt | Pleopeltis polypodioides ssp. polypodioides | Polypodiaceae
|
| POPS5 | Polypodium pseudoaureum Cav. | Phlebodium pseudoaureum | Polypodiaceae
|
| POPS4 | Polypodium pseudogrammitis Gaud. | Grammitis tenella | Grammitidaceae
|
| POPTC | Polypodium ptilodon Kunze var. caespitosum (Jenman) A.M. Evans | Pecluma ptilodon ssp. caespitosum | Polypodiaceae
|
| PORE11 | Polypodium repens Aubl. | Campyloneurum repens | Polypodiaceae
|
| POSA15 | Polypodium saffordii Maxon | Lellingeria saffordii | Grammitidaceae
|
| POSA24 | Polypodium sarmentosum Brack. | Adenophorus pinnatifidus | Grammitidaceae
|
| POSA19 | Polypodium saximontanum Windham | Rocky Mountain polypody | Polypodiaceae
|
| POSC7 | Polypodium scolopendria Burm. f. | Microsorum scolopendria | Polypodiaceae
|