UNUSUAL FORESTS
In addition to the forest types already discussed, a
number of other individual types and species found in the National Park
System are of such great interest that they deserve special mention.
Sequoia.This ancient genus is
represented by two species in Californiathe redwood, Sequoia
sempervirens, along the coast, and the giant sequoia, Sequoia
gigantea, in the Sierra Nevada. The latter species produces the
largest trees in the world, while the redwood, of lesser maximum
diameter, produces the tallest.
The redwood occurs in the fog belt along the
northwest coast of California and extends a short distance into Oregon.
This strip is approximately 450 miles in length and has an average width
of 15 miles. The redwood is represented in the National Park System in
only one areaMuir Woods National Monument, located at the foot of
Mount Tamalpais and approximately 10 miles northwest of San Francisco.
Fortunately, some of the finest of the redwood groves are preserved in
the California State Park System. The redwood is our only coniferous
species that has the habit of reproducing freely by stump sprouts.
The giant sequoia is found only on the western slopes
of the Sierra Nevada, in central California, at elevations of 4,000 to
8,000 feet. The groves are scattered through a narrow belt extending
north and south for a distance of about 250 miles, within which lie
Yosemite, Kings Canyon, and Sequoia National Parks. The General Sherman
Tree, located in Giant Forest in Sequoia National Park, is often
referred to as the oldest and largest living thing. This specimen has a
basal diameter of 30.7 feet and a height of 272.4 feet. Its age has been
variously estimated at 3,000 to 3,500 years.
Standing in the midst of a sequoia grove with its
tremendous tree columns like cathedral pillars reaching to the sky, the
shafts of the sun's rays alternating with the shadows of the tree
trunks, and stillness pervading the scene, one is reverently conscious
of the presence of the Creator in the midst of His glorious
handiwork.
Sugar Pine.Associated with the giant
sequoias in the Sierras, and somewhat larger than the ponderosa pine in
its maximum dimensions, is this white pine species. It is one of the
finest and certainly the most picturesque of the pines, with its greatly
elongated branches, from the ends of which the long cones hang. The
appearance presented has been compared to the apostles with extended
arms bestowing the benediction. The sugar pine attains a diameter of
10 feet at breast height (4-1/2 feet above the ground) and a
height of 245 feet, and reaches an age of 500 years or more.
In addition to its association with the giant
sequoia, the sugar pine extends through other portions of the forests in
Yosemite, Kings Canyon, and Sequoia National Parks. It is found also in
Lassen Volcanic National Park in mixture with ponderosa pine, white fir,
and incense-cedar.
Olympic Rain Forest.Next to the
sequoias, the rain forest of the Olympic Peninsula, in the State of
Washington, is the most spectacular forest type represented in the
National Park System. In this forest there is an association of Sitka
spruce, western redcedar, western hemlock and Douglas-fir, all reaching
large dimensions, with an understory of bigleaf maple, from whose
branches hang draperies of green moss and lichen. The forest floor is
lush and green with a carpet of oxalis, bunchberry dogwood, ferns and
moss, and the whole ensemble, like the sequoia groves, reminds one of a
glorious cathedral. The high rainfall of this sectionup to 140
inches a yearand the equable climate of the lowlands produce a
luxurious verdure which many visitors compare with the tropics.
Saguaro.In strange contrast to the
Olympic rain forest are the saguaro forests of Saguaro and Organ Pipe
Cactus National Monuments in Arizonaleafless forests of massive
columnal cacti spread over the undulating desert. The saguaro is the
product of severe arid conditions under which the plants have survived
by developing water storage organs and by reducing to a minimum the loss
of moisture from their bodies. The stem of the saguaro is composed of a
skeleton of 12 to 30 slender vertical ribs supporting a mass of spongy
tissues. Following soaking rains, the root system of the cactus draws
up immense quantities of water which are absorbed by the spongelike
pulp. A mature plant, with a height up to 50 feet and weighing from 6
to 10 tons, may take up as much as a ton of water following a rain.
During dry weather the saguaro gradually uses its stored water, shrinks
in girth and weight, and develops a wrinkled appearance due to the
drawing together of the vertical ribs. In spring the
fluted columns of the saguaro are crowned with creamy white blooms which
later produce brilliant scarlet fruits that are edible.
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