Common after fires and forms thickets around streams, lakes and in swamps. Alnus sp . H, T, S Throughout Alaska, north of the Brooks Range, south to the beginning of the Alaska Peninsula and in Southeast Alaska. Three of the four alder species reach tree size. Colonizes disturbed sites, floodplains, streambanks, landslides, gravelly slopes and logging roads.
Alders have the capacity to fix nitrogen.
Quaking Aspen Populus tremuloides T, S, R Interior Alaska, north to the south slopes of the Brooks Range, south to the beginning of the Alaska Peninsula, Kenai Peninsula and northern part of Lynn Canal. Fast growing, small to medium sized tree found on south well-drained benches and creek bottoms. Often found in dense stands after fires. Forms root suckers. Birch Betula papyrifera T, S North to the southern flanks of the Brooks Range, west to Unalakleet, east to Canada and south to the Kenai Peninsula and the upper Alaska Peninsula.