Yosemite Natural History
- High Country | Glacier Point | Giant
Wawona | Wilderness |
Park embraces a vast tract of scenic wildlands set aside in 1890
to preserve a portion of the Sierra Nevada mountains that stretches
along California's eastern flank. The park ranges from 2,000 feet
above sea level to more than 13,000 feet and offers three major
features: alpine wilderness, groves of Giant Sequoias, and Yosemite
The 200 miles of roads give access
to all of these features either by car or by free shuttle bus in
some areas. To get to know the real Yosemite, however, you must
leave your car and take a few steps on a trail. You don't have to
walk far to discover the grandeur that can be found here and the
values this special place offers. Millions of people have come to
Yosemite and left refreshed and relaxed and perhaps a bit more knowledgeable
about what they want out of life. See what you can find.
The story of Yosemite began about
500 million years ago when the Sierra Nevada region lay beneath
an ancient sea. Thick layers of sediment lay on the sea bed, which
eventually was folded and twisted and thrust above sea level. Simultaneously
molten rock welled up from deep within the earth and cooled slowly
beneath the layers of sediment to form granite. Erosion gradually
wore away almost all the overlying rock and exposed the granite.
And even as uplifts continued to form the Sierra, water and then
glaciers went to work to carve the face of Yosemite. Weathering
and erosion continue to shape it today.
Tuolumne Meadows and the High Country
This section of Yosemite has some
of the most rugged sublime scenery in the Sierra. In summer the
meadows, lakes, and exposed granite slopes teem with life. Because
of the short growing season, the plants and animals take maximum
advantage of the warm days to grow, reproduce, and store food for
the long, cold winter ahead.
The Tioga Road (California 120),
crosses this area. This scenic highway, originally built as a mining
road in 1882-83, was realigned and modernized in 1961. The road
passes through an area of sparkling lakes, fragile meadows, domes,
and lofty peaks that only 10,000 years ago lay under glacial ice.
Scenic turnouts along the road afford superb views. At Tioga Pass
the road crosses the Sierra's crest at 9,945 feet, the highest automobile
pass in California.
Tuolumne Meadows (at 8,600 feet)
is the largest sub-alpine meadow in the Sierra. It is 55 miles from
Yosemite Valley via the Tioga Road. Long a focal point of summer
activity, it is also growing in popularity as a winter mountaineering
area. In the summer Tuolumne Meadows is a favorite starting point
for backpacking trips and day hikes. The meadows are spectacular
in early summer, abounding in wildflowers and wildlife.
Rangers at the Tuolumne Meadows
Visitor Center, open during the summer, can help you. Remember that
Yosemite’s meadows are fragile and are easily affected by foot traffic
and are closed to bicycles and autos.
A trip into the high country can
be rewarding. But remember that the elevation ranges from 7,000
to 13,000 feet. Even hardy visitors find that vigorous exercise
can make them short of breath. Slow your pace; take time to awaken
your sense of wonder.
Glacier Point [Top]
Glacier Point is one of those rare
places where the scenery is so vast that it overwhelms the viewer.
Below your feet a sheer rock cliff, about 3,200 feet straight down,
affords you a bird's eye view of the entire Yosemite Valley. Across
the valley you can see the 2,425-foot drop of Yosemite Falls. Beyond,
the panoramic expanse of the High Sierra stands out in awe-inspiring
clarity. Signs identity major peaks. Sunset and full moon nights
are ideal times to visit the point. A full moon transforms the pastel
granite landscape into a fairyland. In summer you can drive to Glacier
Point (32 miles from Yosemite Valley). In winter when the road is
closed at Badger Pass Ski Area Glacier Point is a favorite destination
for cross-country, skiers. But no matter how you travel or when
you go, Glacier Point offers what may be Yosemite's finest view.
Giant Sequoia Groves [Top]
The Mariposa Grove, 35 miles south
of Yosemite Valley, is the largest of three Sequoia groves in Yosemite.
The Tuolumne and Merced Groves are near Crane Flat. Despite human
pressures, these towering trees, largest of all living things, have
endured for thousands of years. Only in recent years, however, have
we begun to understand the Giant Sequoia environment. During the
last 100 years protection has sometimes been inadequate and sometimes
excessive. For example, in the late 1800s tunnels were cut through
two trees in the Mariposa Grove. Conversely, good intentions created
another problem, protection from fire has resulted in adverse effects.
Sequoias are wonderfully adapted
to fire. The wood and bark are fire-resistant. Black scars on a
number of large trees that are still prospering indicate they have
survived many scorching fires. Sequoia reproduction also depends
on fire. The tiny seeds require minimal soil for germination, and
seedlings need sunlight. Historically, frequent natural fires opened
the forest, thinned out competing plant species, and left rich mineral
soil behind. But years of fire suppression have allowed debris,
such as fallen branches, to accumulate, stifling reproduction and
allowing shade-tolerant trees to encroach. Prescribed fires, intended
to simulate natural fires and improve the health of the forest,
are now set by the National Park Service.
As you look at these trees, keep
in mind that they have been here since the beginning of history
in the western world. The Mariposa Grove's Grizzly Giant is 2,700
years old and is thought to be the oldest of all Sequoias. Private
vehicles are not permitted beyond the parking area in the Mariposa
Grove. You may ride the trams through the Grove from May until October.
Trails are available year-round for hiking or cross-country skiing.
This Indian word apparently meant
"big tree". Wawona was once an Indian encampment and,
later, was the site of a wayside hostel built in 1857 by Galen Clark.
Known as Glares Station, it served as an overnight stop for visitors
in transit between Yosemite Valley and Mariposa. In 1864, when Yosemite
Valley and the Mariposa Grove were set aside for protection, Clark
became the first guardian of the area. In 1875, the year the original
Wawona road opened, the Washburn brothers purchased the area and
built the Wawona Hotel that is still in operation today. Wawona
focuses on Yosemite's human history. It is the setting of the Pioneer
Yosemite History Center, a collection of relocated historic buildings
and horse-drawn coaches.
Yosemite's wilderness is varied and
offers day hiking and backpacking experiences for both the seasoned
hiker and the novice. About 800 miles of trails offer a variety
of climate, elevation, and spectacular scenery. Near the crest of
the Sierra you can take both long and short trips at elevations
above 9,000 feet. The higher regions offer a cool climate, while
lower elevations are warmer and drier.
To protect Yosemite's wilderness,
there are quotas for overnight use. Free wilderness permits are
required and are available at ranger stations and visitor centers.
Be sure to read the information you receive with your permit and
observe all regulations. Above all, remember to keep your impact
to a minimum. Additionally, you will need appropriate equipment
and good footgear.
During winter the wilderness is
receiving increased mountaineering use. Cross-country skiing and
snow-shoeing have grown in popularity and open up a new world for
the backpacker. The high country is a wonderland. Deep snow covers
the land, and summer landmarks may be unrecognizable. But winter
in the wilderness is more demanding than summer. Good equipment,
warm clothing, and proper planning are essential to assure a safe
and comfortable trip into the harsh Sierra winter environment. Backcountry
travel both summer and winter, can be gratifying. However you are
experiencing the mountains on their terms, and the mountains are
not forgiving to the careless or unprepared.
Yosemite Valley [Top]
"The Incomparable Valley",
it has been called, is probably the world's best known example of
a glacier-carved canyon. Its leaping waterfalls, towering cliffs,
rounded domes, and massive monoliths make it a preeminent natural
marvel. These attributes have inspired poets, painters, photographers,
and millions of visitors beginning with John Muir for more than
one hundred years. Nowhere in Yosemite is the sense of scale so
Yosemite Valley is characterized
by sheer walls and a flat floor. Its evolution began when alpine
glaciers lumbered through the canyon of the Merced River. The ice
carved through weaker sections of granite plucking and scouring
rock but leaving harder, more solid portions—such as El Capitan
and Cathedral Rocks—intact and greatly enlarging the canyon that
the Merced River had carved through successive uplifts of the Sierra.
Finally the glacier began to melt and the terminal moraine left
by the last glacial advance into the valley dammed the melting water
to form ancient Lake Yosemite, which sat in the newly carved U-shaped
valley. Sediment eventually filled in the lake, forming the flat
valley floor you see today. This same process is now filling Mirror
Lake at the base of Half Dome.
In contrast to the valley's sheer
walls, the Merced Canyon along California 140 outside the park is
a typical river-cut, V-shaped canyon, for the glaciers did not extend
this far. Back from the rim of the valley itself, forested slopes
show some glacial polish. But for the most part these areas also
were not glaciated.
The valley is a mosaic of open meadows
sprinkled with wildflowers and flowering shrubs, oak woodlands,
and mixed-conifer forests of ponderosa pine, incense-cedar, and
Douglas-fir. Wildlife from monarch butterflies to mule deer and
black boars flourishes in these communities. Around the valley's
perimeter, waterfalls, which reach their maximum flow in May and
June, crash to the floor. Yosemite, Bridalveil, Vernal, Nevada,
and Illilouette are the most prominent of these falls, some of which
have little or no water from mid-August through early fall.
Take time to visit the Valley Visitor
Center, where an orientation slide program and publications are
available. Exhibits highlight the valley's natural and human history.
Rangers are available to answer questions or assist you. The Indian
Cultural Exhibit and the Indian Village, located behind the visitor
center, display the cultural history of the native Miwok and Paiute
people from 1850 to the present. Nearby, the Museum Gallery features
artwork of past and current Yosemite artists.
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