Plants with white flowers
 Monotropa uniflora (Indian-Pipe) |
 Montia linearis (Linear-leaved Springbeauty) |
 Myosurus minimus (Least Mousetail) |
 Myriophyllum sibiricum (Northern Water-milfoil) |
 Navarretia leucocephala (Pincushion Plant) |
 Nymphaea leibergii (Small White Waterlily) |
 Oenothera cespitosa (Gumbo Evening Primrose)) |
 Oenothera nuttallii (White Evening Primrose) |
 Onosmodium bejariense var occidentale (Western False Gromwell) |
 Orobanche fasciculata (Clustered Broom-rape) |
 Orobanche uniflora (One-Flowered Cancer Root) |
 Orthilia secunda (One-Sided Wintergreen) |
 Osmorhiza berteroi (Western Sweet Cicely) |
 Osmorhiza depauperata (Blunt-Fruited Cicely) |
 Osmorhiza longistylis (Long-Styled Sweet Cicely) |
 Parnassia glauca (Glaucous Grass of Parnassus) |
 Parnassia palustris (Grass of Parnassus) |
 Pedicularis lanceolata (Swamp Lousewort) |
 Penstemon albidus (White Beardtongue) |
 Perideridia gairdneri (Squawroot) |
 Persicaria lapathifolia (Pale Persicaria) |
 Petasites frigidus (Coltsfoot) |
 Phlox alyssifolia (Blue Phlox) |
 Phlox hoodii (Moss Phlox) |
 Plagiobothrys scouleri (Scouler's Popcornflower) |
 Plantago patagonica (Pursh's Plantain) |
 Platanthera dilatata (White Bog Orchid) |
 Platanthera orbiculata (Round-Leaved Bog Orchid) |
 Polanisia dodecandra (Clammyweed) |
 Polygala alba (White Milkwort) |
 Polygala senega (Seneca Snakeroot) |
 Polygala verticillata (Whorled Milkwort) |
 Polygonum achoreum (Striate Knotweed) |
 Polygonum aviculare (Common Knotweed) |
 Polygonum polygaloides ssp. confertiflorum (White-Margined Knotweed) |
 Polygonum polygaloides ssp. kelloggii (Small Knotweed) |