| § Nama hispidum | Bristly Nama |
| § Neolloydia conoidea | Texas Cone Cactus |
| § Nerisyrenia camporum |  Bicolor Fanmustard |
| § Nicolletia edwardsii | Edwards Hole-in-the-sand Plant |
| § Nicotiana glauca | Tree Tobacco, Tronadora |
| § Nicotiana obtusifolia v. obtusifolia | Desert Tobacco |
| § Nolina erumpens | Beargrass, Foothills Nolina |
| § Nolina microcarpa | Beargrass, Sacahuista |
| § Nolina texana | Texas Bear Grass |
| § Notholaena standleyi | Star Cloak Fern |
| § Nyctaginia capitata | Scarlet Muskflower |
| § Oenothera albicaulis | Prairie Evening Primrose |
| § Oenothera brachycarpa | Shortfruit Evening Primrose |
| § Oenothera caespitosa | Tufted Evening Primrose |
| § Oenothera coronopifolia | Sand Evening Primrose |
| § Oenothera kunthiana | Kunth's Evening Primrose |
| § Oenothera organensis | Organ Mts. Evening Primrose |
| § Oenothera primiveris | Desert Evening Primrose |
| § Oenothera rosea | Limpia Evening Primrose |
| § Oenothera speciosa var. berlandieri | Mexican Evening Primrose |
| § Oenothera stubbei | Baja Evening Primrose |
| § Opuntia engelmanni | Engelmann's Prickly Pear |
| § Opuntia grahamii | Graham's Prickly Pear |
| § Opuntia imbricata | Cane Cholla |
| § Opuntia kleiniae | Klein Cholla |
| § Opuntia macrocentra | Purple Prickly Pear |
| § Opuntia rufida | Blind Prickly Pear |
| § Opuntia schottii | Dog Cholla |
| § Opuntia sp. | Cane Cholla |
| § Parkinsonia aculeata | Retama |
| § Paronychia jamesii | James Nailwort |
| § Parthenium confertum | Lyreleaf Parthenium |
| § Parthenium incanum | Mariola |
| § Pavonia lasiopetala | Rock Rosemallow |
| § Penstemon ambiguus | Sand Penstemon |
| § Penstemon baccharifolius | Shrubby Penstemon, "Del Rio" |
| § Penstemon barbatus | Scarlet Bugler |
| § Penstemon cardinalis | Cardinal Penstemon |
| § Penstemon fendleri | Fendler Penstemon |
| § Penstemon havardii | Big Bend Beardtongue |
| § Penstemon pseudospectabilis | False Spectacular Penstemon |
| § Penstemon superbus | Superb Penstemon |
| § Penstemon thurberi | Thurber's Penstemon |
| § Penstemon wrightii | Wright's Penstemon |
| § Phacelia integrifolia | Gypsum Phacelia, Texan Phacelia |
| § Phacelia popei | Pope's Phacelia |
| § Phlox mesoleuca | Threadleaf Phlox |
| § Phyla nodiflora | Turkey Tangle Fogfruit |
| § Pinus engelmannii | Apache Pine |
| § Pinus remota | Papershell Pinyon |
| § Pistacia texana | Texas Pistache, Lentisco |
| § Plantago helleri | Heller's Plantain |
| § Plantago patagonia | Patagonian Plantain |
| § Plumbago scandens | Plumbago, "Summer Snow" |
| Poliomintha glabrescens | Rosemary Mint |
| § Poliomintha incana | Desert Rosemary |
| § Poliomintha madrensis | Madrean Rosemary |
| § Polygala alba | White Milkwort |
| § Porophyllum scoparium | Poreleaf |
| Proboscidea Plant Data Sheet | Devil's Claw |
| § Prosopis glandulosa | Honey Mesquite |
| § Prosopis pubescens | Screwbean Mesquite |
| § Prunus mexicana | Mexican Plum |
| § Prunus serotina var. virens | Southwestern Chokecherry |
| § Psilostrophe tagetina | Woolly Paperflower |
| § Psorothamnus scoparius | Broom Dalea |
| § Purshia mexicana | Mexican Cliffrose |
| § Quercus arizonica | Arizona White Oak |
| § Quercus emoryi | Emory Oak |
| § Quercus gravesii | Chisos Red Oak |
| § Quercus grisea | Gray Oak |
| § Quercus hypoleucoides | Silverleaf Oak |
| Quercus muhlenbergia | Chinkapin Oak |
| Quercus oblongifolia | Mexican Blue Oak |
| Quercus polymorpha | Coahuila Oak |
| § Quercus turbinella | Scrub Oak |
| § Quincula lobata | Purple Groundcherry |
Last Update: 9 Sep 2006