White Alder
Alnus rhombifolia
One of the largest alder species in North America.
Field reference
Family
Betulaceae
Growth rate
Fast
Mature size
40–80 ft tall, 20–40 ft spread
Hardiness zone
6-9
Soil preference
Moist, well-drained soils; stream banks and canyon bottoms
Sun
Full Sun
Pruning window
Late winter
Wood properties
Soft, lightweight; not used structurally; good for ecological stabilization
Native range
Western United States (California, Oregon, Washington, Idaho)
Green weight
38 lb/ft³
Common questions
How big does white alder get?
White alder can grow up to 80 feet tall, making it one of the largest alder species.
Where does white alder grow naturally?
It grows along streams and canyon bottoms in western North America.
Is white alder good for erosion control?
Yes. It is commonly used to stabilize streambanks and riparian zones.
Does white alder fix nitrogen?
Yes. It improves soil fertility through nitrogen-fixing root symbiosis.
Is white alder used for lumber?
No. Its wood is too soft for structural timber applications.
Related species in Betulaceae
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