Alpine Zone The alpine zone of the Upper Tuolumne Watershed begins near the
9,500 foot elevation and is easily distinguished as above
tree line. No trees grow in this zone due to the harsh climatic conditions.
Short, cool summers with long, cold, and snowy winters are typical at
these elevations. Many exposed granitic outcroppings, talus slopes, and
boulder fields limit the amount of vegetation that grows here. The herbaceous
plants need to flower and produce their seeds quickly during the short,
frost-free period of summer.
Subalpine
Forest
The subalpine forest zone is found from 8,000-9,500 feet, where the climate is cool with a short growing season and long, cold, and snowy winters. The western white pine, mountain hemlock, and lodgepole
pine are found in this forest with many subalpine meadows that flower
from July through August. This zone can be seen from the Tuolumne Meadows
area east to Tioga Pass.
Upper
Montane Forest
The upper montane
forest spans 6,000-8,000 feet, where the climate is characterized by short, moist, cool summers and cold,
wet winters. Snow often blankets these areas from November through June. Pure stands of red fir and lodgepole
pine are typical of this forest. Jeffrey pine, which has bark that smells
like vanilla, and the picturesque western juniper can also be found in
this zone. Lower
Montane Forest
The Lower Montane ecosystem is found in the Tuolumne watershed in areas between 3,000-6,000 feet in elevation. The lower montane forests include trees such as California black oak, ponderosa pine, incense-cedar,
and white fir. Yosemite’s giant sequoia groves including the Tuolumne Groves are also found within this vegetation
zone.
Foothill
Woodland Zone
This is the foothill woodland zone is hot
and dry in the summer with very little or no snow in the winter.
Plants within this zone include chamise, ceanothus, manzanita,
blue oak, interior live oak, and gray pine. These plant communities can be found near Hetch
Hetchy Reservoir. The Lower Watershed
Today the lower reaches of the river flows
through both urban and rural areas. Land use practices, including gravel
mining, urban development, and agriculture have compromised the river’s ability
to support a vibrant community of plants and animals in some areas. However, several distinct ecosystems can still
be found including the Valley Foothill
Riparian Forest.
This ecosystem includes the community of plants and animals
that live adjacent to the river. In its
natural state, it is a dense tangled mass of water-loving vegetation including
majestic stands of Fremont Cottonwood, Valley Oak, California Black Walnut and
Box Elder that tower over an understory of willows, blackberries, wild grape
and grasses. The lower Tuolumne River
once hosted an extensive track of this riparian forest much of which today has
fallen victim to growing urban settlement and extensive agriculture in the
area. Where it does still exist, an
abundance of wildlife can be found. |
