Definition
The 'mountain alder' (*Alnus viridis* subsp. *sinuata*), also known as Sitka alder, is a shrubby alder species found in mountainous regions of western North America. It often grows in dense thickets along streams and in avalanche zones. It's known for its ability to stabilize steep slopes. Think of it as the 'mountaineer' of the alder world. The leaves are typically oval-shaped with serrated edges. It provides important habitat for wildlife in high-altitude environments.