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 13 black spruce monoculture DHJanzen101146.jpg high resolution
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| Dropping down to the Arctic Circle, near Fairbanks, Alaska, we move back into the land of black spruce forests and where the snow actually melts off completely for as long as three months (though permafrost remains). This entire forest is a single species of tree, though there are a few leafless willow stems in the foreground. This is a normal spring day (1 April) and this will not be a snow-free landscape for another two months. As a general rule, the forest is black spruce on the flat, waterlogged (in summer) and permafrost underlain soils, while some of the slopes (see below in image DHJanzen101147.jpg) have as many as two other species of tree. Yes, this is a three species forested landscape. For contrast, a tropical view of this size could have several hundred species of trees in it and a huge variety of life forms (though it should be added that there are some tropical forests - such as mangrove forests in saline sites - that are equally poor in tree species). | ||
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