Sitka Alder
Alnus viridis subsp. sinuata
Sitka alder colonizes some of the harshest, most disturbed ground in the mountains — avalanche paths, landslides, and glacial outwash — fixing nitrogen in its roots just like its lowland cousin, red alder, to rebuild fertility in raw soil.
Where found
Avalanche chutes, streambanks, and subalpine slopes throughout the Cascades and coastal mountains.
Fun facts
- Often the first woody plant to recolonize avalanche chutes and landslide scars.
- Like red alder, it partners with nitrogen-fixing bacteria in root nodules.
- Grows as a many-stemmed shrub or small tree, rarely with a single dominant trunk.
Specs
| Height | 3–10 m |
|---|---|
| Spread | 3–6 m |
| Lifespan | 40–60 yrs |
| Growth Rate | Fast |
| Sun | Full sun |
| Native Range | Alaska south through the Cascades and Rockies to California |
