Habit: this deciduous tree is medium sized, symmetrical in shape, growing about half as wide as it is tall. The young bark is thin, smooth, and gray-green becoming gray-brown, thick and furrowed with age. The olive green leaves are large, pinnately compound with 5-7 leaflets each reaching up to 5 in. (12 cm) long, margins are smooth, and the underneath side is covered in short hairs. Male and female flowers are found on separate trees in clusters blooming before leaves appear in spring, fruit on female trees is a one winged samara. Leaves turn a vivid yellow in the fall.
Ecology: Oregon ash prefers the damp, loose soils, of riparian zones, and places that are occasionally flooded. It grows from sea level to 3000 ft (910 m) in elevation, and up to 5577 ft (1700 m) in it’s southern range in California.
Growing Conditions: full sun to partial shade in poorly drained moist to wet soil, roots are shallow and spreading.
Oregon ash is the only native Fraxinus to the Pacific Northwest. Great for revegetating wet areas. Used by wildlife for food and shelter. Birds, squirrels, and an occasional mouse consider the seeds a delicacy.