The otherwise similar Sorbus scopulina has yellow-green sharp-pointed leaflets that are sharply serrated over most of their length.
Winter buds
Not sticky with rusty hairs.
Leaves
Alternate, compound, six to ten inches long, Leaflets seven to ten, blue-green, lanceolate or long oval, with rounded tip, toothed usually from the middle to the end. In autumn they turn yellow, orange and red. Stipules leaf-like, caducous.
Flowers
After the leaves are fully grown, June through September.[3] White, small, 80 or fewer, borne in flat compound cymes three or four inches across.
Fruit
Berry-like pome, globular, one-quarter of an inch across, bright pinkish[4] red, borne in cymous clusters. They are enjoyed by the
Richardson's grouse.[5]
Uses
While not choice eating, the fruits are consumed by some birds in winter.[6]
References
^USDA, NRCS (n.d.).
"Sorbus sitchensis". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team. Retrieved 24 November 2015.
^Pojar, Jim; Andy MacKinnon (1994). Plants of the Pacific Northwest. Lone Pine Publishing. p. 71.
ISBN1-55105-042-0.
^Sullivan, Steven. K. (2013).
"Sorbus sitchensis". Wildflower Search. Retrieved 2013-03-17.
^McAllister, H.A. 2005. The genus Sorbus: Mountain Ash and other Rowans . Kew Publishing.