| Family | ROSACEAE |
| Genus species | Petrophytum cinerascens (Piper) Rydb. |
| Bibliography | N. Amer. Fl. [N.L.Britton & al., eds.] 22: 253 (1908) |
| Native Range | Washington |
| Primary Biome | Temperate |
| Habitat | rocks |
| Altitude | 200-600m |
| Description | leaves oblanceolate-spathulate, 10-25mm, 3-veined, sparsely appressed pubescent, floral stems with numerous linear bracts, raceme spicate, 2-6cm long, petals minute |
| Size | 5-10cm |
| Color | white |
| Bloom | summer |
| Ca | + |
| Type | shrub |
| Cultivation | sunny rock crevices, protection against winter wet alpine house, poor, drained soil, sun |
| Propagation | seed in winter, germ. 1-3 months, 16-18°C cuttings in late summer |
| Synonyms | Luetkea cinerascens (Piper) A.Heller Spiraea cinerascens Piper |
| Territory | 7 Northern America 73 Northwestern U.S.A. (WAS Washington) |