Mountain Alder
Alnus incana subsp. tenuifolia
Important riparian stabilizer and nitrogen-fixing pioneer species.
Field reference
Family
Betulaceae
Growth rate
Fast
Mature size
15–30 ft tall, 10–25 ft spread
Hardiness zone
2-6
Soil preference
Moist to wet soils; riparian zones, mountain streams
Sun
Full Sun to Partial Shade
Pruning window
Late winter
Wood properties
Soft, lightweight; important for soil stabilization rather than timber
Native range
Western North America (Rockies, Pacific Northwest, Alaska)
Green weight
38 lb/ft³
Pests & diseases to watch
Common questions
Where does mountain alder grow?
It grows along streams and mountain riparian areas across western North America.
Is thinleaf alder good for erosion control?
Yes. It is widely used to stabilize streambanks and disturbed soils.
Does mountain alder fix nitrogen?
Yes. Like other alders, it enriches soil through nitrogen fixation.
How large does thinleaf alder grow?
It typically reaches 15 to 30 feet tall depending on site conditions.
Is mountain alder fast growing?
Yes. It is a fast-growing pioneer species in moist environments.
Related species in Betulaceae
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