Through a series of complex vegetation stages, each characterized by
different herbs, trees, and shrubs, the forest slowly returns to the
type of vegetation best suited to the physical and climatic conditions
of the site; this is called a climax community. The fact that most of
Glacier’s forests are in some stage of recovery from fire accounts in
part for the mosaic of forest cover found here.
The forest of Huckleberry Mountain on the Camas Creek road was consumed
in the 1967 fire. By 1969, among the charred, lifeless trunks of the
former forest, lush grass and sunloving fireweed, thistle, and
paintbrush were growing. And by 1974 lodgepole pine seedlings along the
road were a meter or two high. Lodgepole is a fast-growing tree that
requires full sun to germinate. Forest fire is necessary for the
regeneration of these trees: the intense heat causes the tightly closed
cones to open, releasing the seeds that will establish the forest. So
young pines developed among fireweed, spiraea, willow, and mountain
maple shrubs.
The lodgepole forest near the western entrance to the park has been
developing since 1929, when fire destroyed the redcedar-hemlock forest
in the area between Apgar and West Glacier. Beneath the scattered spires
of old larch that survived the burn, the lodgepoles have now grown up,
forming a canopy that shades the forest floor. Because lodgepole live
only about 80 years and will not germinate in shade, this forest will
not exist long. Shade-tolerant Douglas-fir, white pine, Engelmann spruce
and western redcedar seedlings are now taking hold. But the physical
characteristics of this area—the climate, terrain, and soil—are
ultimately most favorable for western redcedar and hemlock; and unless
other disruptions intervene, this area will eventually again become a
dense redcedar-hemlock forest.
But this will not happen quickly. The soil after hundreds of years of
collecting debris will again become rich and moist. Young hemlocks will
germinate on and near decaying logs. When old larches, firs, and pines
fall, the slow-growing redcedars and hemlocks will take their places in
the canopy.
Forest succession is a more complicated story than this; it is a
fascinating study involving herbs, shrubs, small and large trees, and
animal populations. From location to location it will vary; only in its
broad outlines is it predictable. It is based on the observation that,
given time, a forest—or any other plant community—will progress until it
reaches climax—that is, the stage that will perpetuate itself.
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How then are we to think about fire? Increasingly, experts are concerned
not so much with fire suppression as with fire management. For
suppression has at least three disadvantages: it allows the accumulation
of unburned fuels that can result in “fire storms” when they are finally
ignited; an undiversified climax forest is more vulnerable to disease
than is a mixed forest; and a dense forest canopy discourages shrub
growth, an important food source for deer, wapiti, moose, and smaller
animals.
As the well-being of the deer herd depends on the predators that thin
its numbers, so the long-term well-being of the forest depends on fire
to rejuvenate it periodically. We must realize that wilderness is
identified with fire, landslide, avalanche, windfall, and flood. Nature
not only has learned to cope with these agents of change—she depends
upon them for maintaining the delicate balances between landscape and
life. There is in the business of nature, after all, more than the
pleasing of man’s eye.