Sitka Mountain Ash
Sorbus sitchensis
Rosaceae · broadleaf · native
Sitka mountain ash is a deciduous shrub or multi-stemmed small tree reaching 20 feet (though only 1-2 m tall at high elevations), native from southwest Alaska south along the Pacific Coast and through the Cascade Range to northern California, and east to Idaho and Montana.
Sitka mountain ash prefers partial shade to full sun on moist, well-drained soils; it is shade-tolerant in its native temperate rainforest habitat. Provide consistent moisture during establishment; once settled, the plant is drought tolerant. The orange-red berries that mature in fall are excellent food for birds and wildlife.
Quick Facts
Height
20 ft
Light
Full Sun to Shade
Hardiness
Zone Zones 5a–8b
Origin
Pacific Northwest native
Diseases (5)
Pests (10)
Cinara occidentalis, Cinara abietis Aphid
Apple-and-thorn skeletonizer
Enarmonia formosana Cherry bark tortrix
Mountain ash sawfly
Caliroa cerasi Pear sawfly (pear slug)
Phytoptus pyri Pearleaf blister mite
Cylindrocopturus furnissi Root weevil
Malacosoma spp. Tent caterpillar
Leaf blister mite
Ash borer