A Bit of Canada Stranded in the Smokies
Vegetation to Great Smoky Mountains National Park is
what granite domes and waterfalls are to Yosemite, geysers are to
Yellowstone, and sculptured pinnacles are to Bryce Canyon National Park. There
being no timberline in the southern Appalachian Mountains plants are
practically everywhere; in this regard the Great Smokies have an
appearance quite unlike the higher ranges of the Far West where great
expanses of barren, or mostly barren, rock are characteristic. The
low-altitude clearings made by white man during the 19th and early 20th
centuries are rapidly reverting to forest. For
this reason, more than 95 percent of the park's 800
square miles is now dominated by forests. Since almost 40 percent of the
forests is essentially unaltered, this represents probably the finest
wilderness area in the eastern half of the United States. More than
1,300 kinds of flowering plants, almost 350 mosses and liverworts, 230
lichens, and more than 2,000 fungi have been found here.
At high altitudes, forests of red spruce represent
the Canadian zone at its southernmost limit in the Eastern United States.
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Geologists tell us that the Great Smokies remained
above the influence of ancient inland seas which covered vast areas of
our country hundreds of millions of years ago. Neither were they directly
affected by the Pleistocene icefields which extended southward to
southern Ohio. While the continental glaciers made life intolerable
wherever they penetrated, the Great Smoky Mountains served as a haven
for Canadian-zone flora and fauna. In a sense these plants and animals
waited out the great freeze for generation after generation until,
finally, the climate began to moderate, the glaciers began to melt, and
living things began to repopulate what had
been an ice-fettered land. But while some migrated
north in the wake of the retreating ice, others were left stranded in
these higher ranges of the southern Appalachians, inching their way to
higher and higher ground as the warming cycle continued. And such is the
trend which has continued down to our time. Present-day man is living
out his time in a warming interval which appears destined to continue
its inroads upon the icefields of northern North America while it
shrinks the glaciers remaining in the highest Sierras and in the Rockies
and while it whittles away at the lower fringes of the dwindling
spruce-fir forests in the Smokies. Essentially the uplands of the Great
Smokies are a kind of Canadian island left stranded in the sky by
climatic changes.
Cones of the Fraser fir disintegrate on the branches when mature.
However, they are frequently harvested, when green, by the red
squirrels. No other tree in the park has upright cones.
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A warming cycle tends to reduce slowly the extent of
the Canadian-zone forests of the southern Appalachian Mountains. But
mankind has accelerated the pace a thousandfold so that now only about
one-tenth of the original stand of spruce remains. (See "Selected
Bibliography," Korstian, 1937.) Fortunately, an excellent representation
crowns the highest peaks of the park, where it has permanent
sanctuary. Gatlinburg, Tenn., and Cherokee, N.C., are communities
located on the north-central and south-central boundaries of the park,
respectively. A motorist starting at either of these communities can be
in a Canadian environment in 30 minutes, not only as far as the
vegetation is concerned but also from the standpoint of the dominant
birds and mammals. Even many of the insects are identical with, or
closely related to, northern forms.
The Fraser fir, or "balsam," which comprises the bulk
of the Great Smokies' forests on mountains exceeding 6,000 feet, appears
very similar to the balsam fir of northern New England and Canada.
Botanically, the two species are distinct. The Fraser fir is readily
distinguished from the red spruce, which often grows associated with it,
by its upright cones and by the blunt aromatic needles which are green
above and lined with gray below. A scattering of blisters is evident in
the bark of many of these trees. The red spruce grows to greater height
and diameter; its cones are pendant, the sharp-pointed needles are the
same shade of green above and below, and bark blisters are never
present.
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