(Alnus viridis ssp. sinuata)
Sitka Alder is sometimes called Mountain Alder. This Alder can be found in all places where you find red alder. You can also find it in the Rocky Mountains, Yukon and North West Territories, Greenland and Siberia. It is very similar to Red Alder, an easy way to tell them apart when there are leaves is that Sitka leaves are quite sawtoothed when compared to Red Alder.
Sitka alder is a small tree. They often have multiple stems and often grow in dense thickets. It will thrive in shady conditions as well as high water tables. It is a nitrogen fixer, and this enables the species to stabilize soil on recent slides and stream banks. The species provides cover for nesting birds and food for small animals. Because of its nitrogen-fixing capacity and its positive impact on leaf litter quality and soil fertility, Sitka alder can be referred to as a healing tree species.
This Alder reproduces by seeds; these seeds are very light, and through wind and water, they can travel long distances. They do not have a seed crop every year, but they have one every three to four years. They will sprout through roots and from cut stumps.