Salix petrophila
Rocky mountain willow, Rocky Mountain Willow
(c) Matt Lavin, some rights reserved (CC BY) · licence
Family: Salicaceae · Type: Shrub · Native
Salix petrophila (Rocky mountain willow) is a native California shrub in the Salicaceae family, recognized by but distinctive trailing/rooting habit and soft shaggy hairs.
Rocky mountain willow is a California native shrub found in the Lassen Peak and central Sierra Nevada Mountains in alpine tundra at elevations of 1,670 to 4,000 meters. Flowering from July to August, this plant produces small flowers on leafy shoots with tan to dark brown bracts. Growing as a diminutive trailing shrub less than 10 centimeters tall that roots along the ground, it develops yellow-green or yellow-brown twigs with sparse soft shaggy hairs. Its leaves are elliptic to obovate, 19 to 44 millimeters long, with long soft wavy hairs on the undersides and wedge-shaped bases. The plant has distinctive tiny stipules that are either absent or vestigial, and its mature leaves have a soft, shaggy appearance.
Identification and appearance
Key characters: 13 sympatric species but distinctive trailing/rooting habit and soft shaggy hairs
Habitat and range
Habitat: Alpine tundra
Elevation: 1670-4000 m
California counties: Mono, Inyo, Fresno, Tuolumne, Mariposa, Alpine, Tulare, Madera, Shasta, Sierra, Nevada, Lassen
Outside California: to western Canada, Colorado, New Mexico
Bloom period
Salix petrophila blooms Jul-Aug.
How to tell it apart
vs Umbellularia: Willows have narrow leaves with no scent; crush bay laurel leaf for intense spicy aroma.; vs Baccharis: Willows have catkins; baccharis has fuzzy white seed heads and resinous stems.; vs Acacia: Willow leaves have one central vein; acacia leaves are compound with many small leaflets or modified into flat phyllodes.; vs Quercus: Willows have narrow flexible leaves; oaks have broader stiff leaves and produce acorns.; vs Schinus: Willow leaves are simple; pepper tree has compound leaves with 15-40 leaflets and peppery-scented crushed foliage.
Frequently asked questions
Is Salix petrophila native to California?
Yes. Salix petrophila is native to California (recorded as native).
When does Salix petrophila bloom?
Salix petrophila blooms Jul-Aug.
Where in California does Salix petrophila grow?
Salix petrophila occurs in Mono, Inyo, Fresno, Tuolumne, Mariposa, Alpine, Tulare, Madera and other counties, at elevations of 1670-4000 m.
What plant family does Salix petrophila belong to?
Salix petrophila is in the Salicaceae family, genus Salix.
What habitat does Salix petrophila grow in?
Salix petrophila grows in Alpine tundra.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.