Alnus viridis subsp. sinuata

Thinleaf or sitka alder, Thinleaf Or Sitka Alder

Family: Betulaceae · Type: shrub · Native

Thinleaf alder is a native shrub found in the Klamath Ranges, northern coastal ranges, and western Cascade Range near Grizzly Peak in Shasta County, growing along creeks, seeps, and meadow margins at elevations of 1,000 to 2,700 meters. Flowering in spring, this plant produces small catkin-like flowers typical of alders. Growing with multiple trunks up to 8 meters tall, it forms dense thickets in moist mountain environments. Its thin leaves are distinctively ovate with sharply serrated edges, displaying a shiny yellow-green surface on the upper side and a green underside with occasional hair clusters along the major veins. The shrub is lightly to moderately resinous, with leaf bases that range from tapered to slightly heart-shaped and tips that taper to a sharp point.

Habitat: Along creeks, seeps, meadow margins

Bloom period: Spring

Elevation: 1000-2700 m

Bioregions: KR, NCoRO, NCoRH, w CaRH (Grizzly Peak, Shasta Co.)

California counties: Del Norte, Trinity, Humboldt, Siskiyou, Shasta

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.