B
Vegetation
Boreal forest composition varies greatly throughout its circumpolar range in response to differences in current environment and histories. Primary species include broad-leaved deciduous trees, needle-leaved evergreens, and needle-leaved deciduous trees. In Alaska, the predominant conifers are white (Picea glauca) and black spruce (Picea mariana).
Important deciduous trees are aspen (Populus tremuloides), poplar (Populus balsamifera), and birch (Betula neoalaskana). Larch (Larix laricina) tends to be found in local populations. Pine is absent in Interior Alaska but a prominent component of the boreal forest to the east in the Yukon and Northwest Territories of Canada. Dominant shrubs include alder and willow. The boreal forest has fewer vascular plant species than any other forested biome, but a rich flora of mosses and lichens.
