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People have been destroying forests for
hundreds of years, but the rate of destruction has been increasing so rapidly that some forests won't last much longer. Some areas, such as
the American Southeast, that were cut a century ago are now recovering gradually. However, much of the choice timber is now gone and
these "new" Southeast forests, which are only beginning to re-grow, are once again being cut. More remote areas are also being logged
heavily, often to supply the growing market for wood-chip products. Coastal temperate forests in Chile, which are home to over 700
species of plants are being cut for this reason. Remote forests in Russia are also being cut, mostly for raw logs. About one fifth of the
world's forests are found in Russia. In some cases, these logs are not allowed to be shipped to North America because of fears
that species of insect pests might also be unknowingly imported.
When attacked by pests or diseases, often it is only one species of tree in a forest that is severely affected, and others remain healthy. Photo by Maya Walters. |
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Trees are, of course, also threatened by more "natural" causes, such as pests and diseases. However, pests and diseases have been around for as long as the forests themselves, and the forests didn't begin to seriously decline until threatened by humans. In large numbers, insects can kill trees, often by eating their leaves. Diseases can wipe out entire populations of tree species. For example, in eastern forests, all the large American chestnut trees were killed back to the roots. However, the blight that killed them did not naturally occur in North America; it was brought, accidentally, by humans. |
threats to forests -- page 5 of 6
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sub-topics
[deforestation] [climate change] [loss of biodiversity] [pollution] [erosion] [fire]
related topics
[forests through time] [biodiversity] [forest types] [wood & forest products] [pests]
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