Introduction
Fire
is a common disturbance in many of the world’s forests.
It renews and maintains the character of the ecosystem, although humans
often perceive it as a disaster that needs to be prevented.
The exclusion of fire from forests has led in some instances to undesirable side effects, as illustrated by the Ponderosa pine forests of western North America. These tend to experience ground fires often, which makes the fires less intense, therefore killing very few overstory trees. A consequence of the suppression of fire in this system is shown by outbreaks of the spruce budworm, due to the invasion of fir trees (their hosts), a fire intolerant species.
Fires are often patchy creating a mosaic of vegetation in different stages of succession. This tends to enhance diversity by providing many different types of habitat for various animals and plants.
