These shrubs provide shade that reduces soil temperatures, allowing spruce and other genera to establish. Can be a major competitor of conifer seedlings . Dense thickets can prevent conifer establishment over large areas. However, due to its nitrogen-fixing ability, alder can improve soil fertility. Survives fire through persistent root crowns.
Fire kills the aboveground portion of the plant.
Root crowns in the mineral soil burn only under the most severe conditions, but they can be killed by the heat generated during a fire. Severe fires that remove the organic layer and expose and char root crowns can completely eliminate sprouting. Considered a survivor species, sprouting from basal or underground parts following fire. Additionally, its wind-dispersed seeds quickly colonize bare mineral soils exposed by fire. Regeneration from sprouting and the establishment of seedlings allow reestablishment at a fairly rapid rate following fire.