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40 North American Natural Resources: Timber and Forest Products
Trees play a vital role in the water cycle, returning water vapor to the atmosphere
through the process of transpiration. Many deforested areas become almost desert-
like over time. Trees and other plant species in a forest absorb carbon dioxide, a
greenhouse gas, from the atmosphere. Cutting the trees not only reduces the amount
of carbon dioxide that can be removed from the atmosphere, it also actually releases
carbon dioxide. The trees hold carbon dioxide, and when they die, the gas is released.
Overall, the impact that clear-cutting a forest has on the habitat, ecosystem, and
climate can be significant.
Forest Fires
Watch the news during the summer months, and you’re almost guaranteed to
see a story about firefighters battling a massive forest fire, usually in the western
parts of the United States. We are conditioned to expect that when there is a fire,
it will be fought. Minimizing the damage done by fire is the goal of all firefighters
everywhere, right?
Maybe not. When it comes to managing forest resources, sometimes a fire is
a good thing. Suppose fires have been fought and stopped in a particular forest
for years. The trees have built up and are now becoming stressed due to a lack
of resources. A thick underbrush of shrubs and smaller plants crowd the forest
floor, blocking sunlight from smaller species and using nutrients from the soil.
Species of plants that depend on fire disappear. Dead and decaying logs and other
material builds up in the forest. The next time lightning strikes a tall tree, that fuel
lying around erupts into a massive forest fire—one that can’t be easily controlled
and could endanger not only the forest, but also the people in the area and the
firefighters.
The approach of fighting every forest fire to the end is not necessarily the best
for the forest.
In the 1900s, the policy in the United States was to fight each and
every forest fire so as to minimize the impact on the environment. It was in the
1960s that this policy began to be questioned, as people understood more about the
role that fire plays in the health and growth of a forest. Today, wildfires and forest