| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| PUPU3 | Puccinellia pumila (Vasey) A.S. Hitchc. | dwarf alkaligrass | Poaceae
|
| PUPU | Puccinellia pumila auct. non (Vasey) A.S. Hitchc. | Puccinellia tenella ssp. alaskana | Poaceae
|
| PURE | Puccinellia retroflexa (W. Curtis) Holmb. | Puccinellia distans ssp. distans | Poaceae
|
| PURU | Puccinellia rupestris (With.) Fern. & Weatherby | British alkaligrass | Poaceae
|
| PUSI2 | Puccinellia sibirica Holmb. | Puccinellia distans ssp. borealis | Poaceae
|
| PUSI | Puccinellia simplex Scribn. | California alkaligrass | Poaceae
|
| PUSU | Puccinellia sublaevis (Holmb.) Tzvelev | smooth alkaligrass | Poaceae
|
| PUSU3 | Puccinellia suksdorfii St. John | Puccinellia distans ssp. distans | Poaceae
|
| PUTEA | Puccinellia tenella (Lange) Holmb. ssp. alaskana (Scribn. & Merr.) Tzvelev | tundra alkaligrass | Poaceae
|
| PUTEL | Puccinellia tenella (Lange) Holmb. ssp. langeana (Berlin) Tzvelev | tundra alkaligrass | Poaceae
|
| PUTET | Puccinellia tenella (Lange) Holmb. ssp. tenella | tundra alkaligrass | Poaceae
|
| PUTE | Puccinellia tenella (Lange) Holmb. | tundra alkaligrass | Poaceae
|
| PUTR | Puccinellia triflora Swallen | Puccinellia andersonii | Poaceae
|
| PUVA | Puccinellia vaginata (Lange) Fern. & Weatherby | sheathed alkaligrass | Poaceae
|
| PUVA3 | Puccinellia vahliana (Liebm.) Scribn. & Merr. | Vahl's alkaligrass | Poaceae
|
| PUWR | Puccinellia wrightii (Scribn. & Merr.) Tzvelev | Wright's alkaligrass | Poaceae
|
| PUCCI | Puccinellia Parl. | alkaligrass | Poaceae
|
| PUHI3 | Pueraria hirsuta (Thunb.) C. Schneider | Pueraria montana var. lobata | Fabaceae
|
| PULOT | Pueraria lobata (Willd.) Ohwi var. thomsonii (Benth.) Maesen | Pueraria montana var. lobata | Fabaceae
|
| PULO | Pueraria lobata (Willd.) Ohwi | Pueraria montana var. lobata | Fabaceae
|
| PUMOL | Pueraria montana (Lour.) Merr. var. lobata (Willd.) Maesen & S. Almeida | kudzu | Fabaceae
|
| PUMO | Pueraria montana (Lour.) Merr. | kudzu | Fabaceae
|
| PUPH2 | Pueraria phaseoloides (Roxb.) Benth. | tropical kudzu | Fabaceae
|
| PUTH | Pueraria thunbergiana (Sieb. & Zucc.) Benth. | Pueraria montana var. lobata | Fabaceae
|
| PUERA | Pueraria DC. | kudzu | Fabaceae
|
| PUBI | Pugiopappus bigelovii Gray | Coreopsis bigelovii | Asteraceae
|
| PUAR2 | Pulicaria arabica (L.) Cass. | ladies' false fleabane | Asteraceae
|
| PUDY | Pulicaria dysenterica (L.) Bernh. | meadow false fleabane | Asteraceae
|
| PUHI2 | Pulicaria hispanica (Boiss.) Boiss. | Pulicaria paludosa | Asteraceae
|
| PUPA6 | Pulicaria paludosa Link | Spanish false fleabane | Asteraceae
|
| PULIC | Pulicaria Gaertn. | false fleabane | Asteraceae
|
| PUCI | Pulmonaria ciliata James ex Torr. | Mertensia ciliata var. ciliata | Boraginaceae
|
| PUOF | Pulmonaria officinalis L. | common lungwort | Boraginaceae
|
| PUSA2 | Pulmonaria saccharata P. Mill. | Bethlehem lungwort | Boraginaceae
|
| PULMO | Pulmonaria L. | lungwort | Boraginaceae
|
| PUHI | Pulsatilla hirsutissima (Pursh) Britt. | Pulsatilla patens ssp. multifida | Ranunculaceae
|
| PULU | Pulsatilla ludoviciana Heller | Pulsatilla patens ssp. multifida | Ranunculaceae
|
| PUNU3 | Pulsatilla nuttalliana (DC.) Spreng. | Pulsatilla patens ssp. multifida | Ranunculaceae
|
| PUOC | Pulsatilla occidentalis (S. Wats.) Freyn | white pasqueflower | Ranunculaceae
|
| PUPAH2 | Pulsatilla patens (L.) P. Mill. ssp. hirsutissima (Pursh) Zamels | Pulsatilla patens ssp. multifida | Ranunculaceae
|
| PUPAM | Pulsatilla patens (L.) P. Mill. ssp. multifida (Pritz.) Zamels | cutleaf anemone | Ranunculaceae
|
| PUPA5 | Pulsatilla patens (L.) P. Mill. | American pasqueflower | Ranunculaceae
|
| PUVU | Pulsatilla vulgaris Miller | European pasqueflower | Ranunculaceae
|
| PULSA | Pulsatilla P. Mill. | pasqueflower | Ranunculaceae
|
| PUAP | Punctelia appalachensis (Culb.) Krog | | Parmeliaceae
|
| PUBO3 | Punctelia bolliana (Mull. Arg.) Krog | | Parmeliaceae
|
| PUBO4 | Punctelia borreri (Sm.) Krog | | Parmeliaceae
|
| PUDA | Punctelia darrowi (J. W. Thomson) Krog | Flavopunctelia darrowi | Parmeliaceae
|
| PUFL | Punctelia flaventior (Stirton) Krog | Flavopunctelia flaventior | Parmeliaceae
|
| PUHY | Punctelia hypoleucites (Nyl.) Krog | | Parmeliaceae
|
| PUMI | Punctelia missouriensis G. Wilh. & Ladd | Punctelia punctilla | Parmeliaceae
|
| PUPE | Punctelia perreticulata (Rasanen) G. Wilh. & Ladd | | Parmeliaceae
|
| PUPR | Punctelia praesignis (Nyl.) Krog | Flavopunctelia praesignis | Parmeliaceae
|
| PUPU2 | Punctelia punctilla (Hale) Krog | | Parmeliaceae
|
| PURE2 | Punctelia reddenda (Stirton) Krog | | Parmeliaceae
|
| PURU2 | Punctelia rudecta (Ach.) Krog | | Parmeliaceae
|
| PUSE | Punctelia semansiana (Culb. & C. Culb.) Krog | | Parmeliaceae
|
| PUSO | Punctelia soredica (Nyl.) Krog | Flavopunctelia soredica | Parmeliaceae
|
| PUST2 | Punctelia stictica (Duby) Krog | | Parmeliaceae
|
| PUSU4 | Punctelia subpraesignis (Nyl.) Krog | | Parmeliaceae
|
| PUSU5 | Punctelia subrudecta (Nyl.) Krog | | Parmeliaceae
|
| PUNCT | Punctelia Krog | punctelia | Parmeliaceae
|
| PUGR2 | Punica granatum L. | pomegranate | Punicaceae
|
| PUNIC | Punica L. | pomegranate | Punicaceae
|
| PUAR3 | Purpusia arizonica Eastw. ex J.T. Howell | Ivesia arizonica var. arizonica | Rosaceae
|
| PUOS | Purpusia osterhoutii A. Nels. | Ivesia arizonica var. arizonica | Rosaceae
|
| PUSA | Purpusia saxosa Brandeg. | Ivesia arizonica var. saxosa | Rosaceae
|
| PUER2 | Purshia ericifolia (Torr. ex Gray) Henrickson | heath cliffrose | Rosaceae
|
| PUGL2 | Purshia glandulosa Curran | desert bitterbrush | Rosaceae
|
| PUMES | Purshia mexicana (D. Don) Henrickson var. stansburiana (Torr.) Welsh | Purshia stansburiana | Rosaceae
|
| PUME | Purshia mexicana (D. Don) Henrickson | Mexican cliffrose | Rosaceae
|
| PUPI | Purshia pinkavae Schaack | Pinkava's cliffrose | Rosaceae
|
| PUST | Purshia stansburiana (Torr.) Henrickson | Stansbury cliffrose | Rosaceae
|
| PUSU2 | Purshia �subintegra (Kearney) Henrickson | | Rosaceae
|
| PUTRG | Purshia tridentata (Pursh) DC. var. glandulosa (Curran) M.E. Jones | Purshia glandulosa | Rosaceae
|
| PUTR2 | Purshia tridentata (Pursh) DC. | antelope bitterbrush | Rosaceae
|
| PURSH | Purshia DC. ex Poir. | bitterbrush | Rosaceae
|
| PYAL | Pycnanthemum albescens Torr. & Gray | whiteleaf mountainmint | Lamiaceae
|
| PYAR | Pycnanthemum aristatum Michx. | Pycnanthemum setosum | Lamiaceae
|
| PYBE | Pycnanthemum beadlei (Small) Fern. | Beadle's mountainmint | Lamiaceae
|
| PYCA | Pycnanthemum californicum Torr. | Sierra mint | Lamiaceae
|
| PYCL | Pycnanthemum clinopodioides Torr. & Gray | basil mountainmint | Lamiaceae
|
| PYCU | Pycnanthemum curvipes (Greene) E. Grant & Epling | stone mountainmint | Lamiaceae
|
| PYFL | Pycnanthemum flexuosum (Walt.) B.S.P. | Appalachian mountainmint | Lamiaceae
|
| PYFL4 | Pycnanthemum flexuosum auct. non (Walt.) B.S.P. | Pycnanthemum tenuifolium | Lamiaceae
|
| PYFL2 | Pycnanthemum floridanum E. Grant & Epling | Florida mountainmint | Lamiaceae
|
| PYHY | Pycnanthemum hyssopifolium Benth. | Pycnanthemum flexuosum | Lamiaceae
|
| PYINI | Pycnanthemum incanum (L.) Michx. var. incanum | hoary mountainmint | Lamiaceae
|
| PYINL | Pycnanthemum incanum (L.) Michx. var. loomisii (Nutt.) Fern. | Pycnanthemum loomisii | Lamiaceae
|
| PYINP | Pycnanthemum incanum (L.) Michx. var. puberulum (E. Grant & Epling) Fern. | hoary mountainmint | Lamiaceae
|
| PYIN | Pycnanthemum incanum (L.) Michx. | hoary mountainmint | Lamiaceae
|
| PYLE | Pycnanthemum leptodon Gray | Pycnanthemum verticillatum var. verticillatum | Lamiaceae
|
| PYLO | Pycnanthemum loomisii Nutt. | Loomis' mountainmint | Lamiaceae
|
| PYMO | Pycnanthemum monotrichum Fern. | onehair mountainmint | Lamiaceae
|
| PYMO2 | Pycnanthemum montanum Michx. | thinleaf mountainmint | Lamiaceae
|
| PYMU | Pycnanthemum muticum (Michx.) Pers. | clustered mountainmint | Lamiaceae
|
| PYNU | Pycnanthemum nudum Nutt. | coastalplain mountainmint | Lamiaceae
|
| PYPI | Pycnanthemum pilosum Nutt. | Pycnanthemum verticillatum var. pilosum | Lamiaceae
|
| PYPU2 | Pycnanthemum puberulum E. Grant & Epling | Pycnanthemum incanum var. puberulum | Lamiaceae
|
| PYPYP | Pycnanthemum pycnanthemoides (Leavenworth) Fern. var. pycnanthemoides | southern mountainmint | Lamiaceae
|
| PYPYV | Pycnanthemum pycnanthemoides (Leavenworth) Fern. var. viridifolium Fern. | southern mountainmint | Lamiaceae
|