Alnus rhombifolia, also known as Sierra Alder or White Alder, is a fast-growing deciduous tree that can reach heights of up to 50 ft. Native to western North America, from Washington east to western Montana and south to California, this tree thrives in riparian zone habitats at an altitude range of 300-8000 ft. It is useful for wet spots in West Coast gardens and can fix nitrogen, making it tolerant to infertile soils. With pale gray bark, smooth on young trees, it becomes scaly on old ones, and the leaves are rhombic to narrow elliptic with a finely serrated margin and a rounded to acute apex. Alnus rhombifolia produces catkins for flowers, and the male ones are slender and yellowish, while the female ones are cone-shaped and woody. The fruit is a leathery, irregularly-shaped samara with a small nut. Some Plateau Indian tribes used white alder for female health treatment needs. Although not well-adapted to fire, white alder regenerates from seed and by sprouting after fire, particularly on moist alluvium left bare from receding floodwaters and on moist mineral soils exposed by fire.