Mountain Hemlock
Tsuga mertensiana
Often grows in extreme high-elevation or snowpack-heavy environments.
Field reference
Family
Pinaceae
Growth rate
Slow
Mature size
50–130 ft tall × 20–35 ft wide
Hardiness zone
4-7
Soil preference
Cool, moist, well-drained acidic soils; snowpack-dependent sites
Sun
Full Sun at elevation; Partial Shade at lower elevations
Pruning window
Late winter (minimal structural pruning)
Wood properties
Light, soft, brittle wood; not commercially important in large-scale timber
Native range
Western North America (coastal Alaska to California Sierra Nevada and Cascades)
Green weight
40 lb/ft³
Common questions
Why is it called mountain hemlock?
It commonly grows at high elevations in mountainous regions.
How tall does alpine hemlock grow?
It can reach 50 to 130 feet depending on site conditions.
Does mountain hemlock tolerate snow?
Yes. It is highly adapted to heavy snowpack environments.
Is alpine hemlock fast growing?
No. It is generally slow-growing, especially in harsh climates.
Where does mountain hemlock grow naturally?
It grows in high-elevation forests of western North America.
Related species in Pinaceae
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