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Vegetation of Bonanza Creek Experimental Forest
The taiga forest of Alaska, part of the circumpolar band of boreal
forest, consists of a mosaic of forest, grassland, shrubs, bogs,
and alpine tundra that have formed primarily as a result of slope,
aspect, elevation, parent material, and succession following disturbance.
In interior Alaska the forest is dominated by young stands in various
stages of succession; mature stands of over 200 years in age are
rare due to frequent fire. In areas relatively protected from fires
such as the river floodplains, the active erosion and meandering
of the silt-laden, glacially fed rivers results in the active production
of newly vegetated silt bars and the rapid erosion of older, mature
stands. Unlike many areas of the world, successional sequences developing
after human disturbances are relatively rare and recent. |
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Vegetation cover map
Species list
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Upland forest types vary from highly productive aspen (Populus
tremuloides Michx.), paper birch (Betula papyrifera Marsh), and
white spruce (Picea glauca (Moench.) Voss) stands on south-facing,
well-drained slopes to permafrost and moss-dominated black spruce
(Picea mariana (Mill.) B.S.P.) forests of low productivity on north-facing
slopes, lowlands, and lower slopes. Floodplain forests of balsam
poplar (Populus balsamifera L.) and white spruce are productive
on recently formed river alluvium where permafrost is absent, but
slow-growing black spruce and bogs occupy the older terraces that
are underlain by permafrost. Approximately 32%, or 42,800,000 ha,
of the total 137,000,000 ha that make up interior Alaska is forested.
Forest land that is considered of commercial value totals about
9,600,000 ha.
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