Pennisetum, 33
Perennial Ryegrass, 29
Perularia, 59
Phalaris, 33
Pharus, 33
Phegopteris, 16
Philotria, 21
Phlebodium, 14
Phragmites, 33
Phymatodes, 14
Physurus, 59
Piaropus, 50
Pickerelweed Family, 50
Pickerelweeds, 50
Pinaceae, 17
Pineapple Family, 48
Pine Family, 17
Pine Fern, 12
Pine Lily, 51
Pine-pink, 57
Pines, 17
Pinus, 17
Pipewort Family, 47
Pipeworts, 47
Pistia, 46
Pityrogramma, 15
Platypus, 59
Pleea, 52
Pleurothallis, 61
Plumegrasses, 27
Poa, 33
Pogonia, 61
Polianthes, 55
Polygonatum, 52
Polypodiaceae, 12
Polypodium, 15
Polypody Ferns, 15
Polypogon, 33
Polyrrhiza, 61
Polystachya, 61
Polystichum, 15
Pond Cypress, 18
Pond Pine, 18
Pondweed Family, 19
Pondweeds, 19
Pontederia, 50
Pontederiaceae, 50
Ponthieva, 61
Potamogeton, 19
Potamogetonaceae, 19
Poverty Grass, 25
Prairie Three-awn, 22


Prairie Wedgegrass, 35
Prescottia, 61
Pseudophoenix, 45
Psilocarva, 43, 44
Psilopsida, 10
Psilotaceae, 10
Psilotum, 10
Psilotum Family, 10
Pteridium, 15
Pteris, 15
Pteris, 15
Pteropsida, 11
Purple Lovegrass, 27
Purple Nut Sedge, 40
Pycnodoria, 15

Quaking Grasses, 23
Quillwort Family, 10
Quillworts, 10

Rabbitfoot Grass, 33
Rattlesnake Fern, 11
Rattlesnake-master, 55
Red-cedars, 18
Red-root, 53
Red Sprangletop, 28
Reed, 33
Reimarochloa, 34
Remirea, 42
Rescue Grass, 24
Resurrection Fern, 15
Rhaphis, 24
Rhapidophyllum, 45
Rhodes Grass, 24
Rhoeo, 49
Rhynchelytrum, 34
Rhynchospora, 42
Ribbon Fern, 14
Rice, 30
Rice Cutgrass, 28
Rosebud Orchid, 58
Rottboellia, 34
Roxburghia Family, 51
Royal Fern, 11
Royal Fern Family, 11
Royal Palm, 45
Roystonea, 45
Ruppia, 19
Ruppiaceae, 19
Rushes, 50
Rush Family, 50
Rush-featherling, 52