Sequoia and Kings Canyon National Parks. Mike White
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a white fir from a red fir, which are similar in appearance, is by examining a tree’s bark. The bark on a mature red fir is maroon-brown, while white fir has grayish bark. Also, the slightly longer needles of the white fir are twisted at the base and have white lines; the shorter red fir needles are four-sided and not twisted.
Red fir prefers deep, well-drained soil and is found in the southern Sierra roughly between 7,000 and 9,000 feet, from Kern County northward. The species thrives in areas receiving the greatest amount or precipitation, usually in the form of winter snowfall.
Animal Life: Inhabitants of the higher elevations of the upper forest zones must adapt to more severe weather conditions and periodically scarce food supplies. Common amphibians in the red fir forest are limited to two varieties each of salamanders, frogs, and toads. Reptiles include the garter snake and three types of lizard.
Ordinary small mammals you might encounter in this zone include the deer mouse, pocket gopher, vole, shrew, broad-handed mole, pika, chipmunk, chickaree, Belding ground squirrel, golden-mantled ground squirrel, northern flying squirrel, beaver, white-tailed jackrabbit, and yellow-bellied marmot. Bats are commonly seen around lakes and meadows in the evening. Medium-size animals include the red fox, porcupine, coyote, long-tailed weasel, fisher, ermine, wolverine, badger, and pine marten. The Sierra bighorn sheep lives in this zone but is very reclusive. Black bear and mule deer are the most common large mammals.
Mule deer (Odocoileus hemionus) are quite numerous in the southern Sierra, since their main predators, the grizzly bear and the wolf, are now extinct in California. Mountain lions are their most common predators today. Starvation and disease are the most common causes of death for mule deer. Mature males may exceed 200 pounds. Each March, males shed their antlers and start to regrow them again in April.
Although not as numerous as in the lower zones, a vast number of birds find a home in the upper forest belt. Among some of the more interesting species are the blue grouse, dipper, and mountain bluebird. The most common (and occasionally obnoxious) bird known to backpackers is the Steller’s jay, whose bold exploits to snatch human food has earned it the nickname “camp robber.”
Lodgepole Pine Forest
Plant Life: Perhaps no tree is more closely associated with the High Sierra than the lodgepole pine. Found between 8,000 and 11,000 feet in the southern Sierra, this versatile conifer with pale gray bark flourishes in soils where red fir struggles because the soil is either too wet or too dry. In stark contrast to the red fir, which is almost exclusively found in California, the two-needled lodgepole pine is one of the most widespread trees in the American West. Typically tall and thin, they reach heights of 50 to 100 feet, and their cones are 1 to 2 inches long.
Although commonly found in exclusive stands, the lodgepole also intermingles with western white pine and whitebark pine in the higher elevations and red fir in the lower elevations. Quaking aspen and lodgepole oftentimes grow together in areas that have plentiful groundwater. On the east side of the range, lodgepole pines are common between 9,000 and 11,000 feet, where the western white pine is the most common associate.
Animal Life: Animals found in the lodgepole pine forest are similar to those found in the red fir forest.
Subalpine Zone
Plant Life: Roughly occurring between 9,500 and 12,000 feet, the subalpine zone straddles the Sierra Crest and bridges the gap between the mighty forest of the lower elevations and the austere realm above timberline.
The most common conifer in this zone is the interesting foxtail pine, with its characteristic pendulous branches. This five-needled pine is similar in appearance to the bristlecone pine. The foxtail pine grows only in Inyo and Tulare Counties in the southern Sierra and in the Klamath Mountains of northern California. Mature specimens reach heights between 20 and 45 feet, and they bear purplish, prickly cones 2 to 5 inches long. Foxtail pines occasionally can be found in pure stands along the eastern fringe of Sequoia National Park and along the Kern River. The most common associate is the majestic whitebark pine, an oftentimes multitrunked tree that survives the harsh conditions just below timberline, sometimes in the form of a windblown shrub. Less common associates include western white, lodgepole, and limber pines.
Forests are but one part of the diverse subalpine zone. Mountain lakes, craggy peaks, and granite-covered slopes are common features of the subalpine landscape, as are numerous grass-and-sedge-covered meadows harboring a vast array of midsummer wildflowers.
Meadow on the Lone Pine Creek Trail (Trip 14)
Animal Life: Animals found in the subalpine zone are similar to those found in the red fir forest.
Alpine Zone
Plant Life: The alpine zone occurs at the highest elevations in the Sierra, where the growing season is measured in weeks rather than months. Harsh conditions characterize this zone, with lower temperatures and cloudier skies allowing snow to linger longer than in other zones, despite the fact that the alpine zone receives less snowfall. At elevations above 12,000 feet, frost can occur at any time during the summer, and cool temperatures, nearly constant winds, and a significant lack of precipitation produce desertlike conditions. Generally poor, granitic soils further limit the number of species able to adapt to this harsh climate.
Most alpine plants have successfully adapted to their environment by developing a low-growing, compact, and drought-tolerant form, which allows them to avoid the full brunt of the wind, grow closer to the warmth of the soil, and survive on low amounts of moisture. Most alpine plants are perennial, using less energy than annuals, which must produce an entirely new plant each season. Vegetation in the alpine zone can be divided into two classifications: alpine meadow and alpine rock.
Alpine meadows are common in the upper realm of the Sierra where a sufficient layer of moist soil is present. Meadows are generally composed of grasses and sedges, with alpine sedge and common sedge the most common. A wide array of wildflowers put on a showy, colorful display over the course of an abbreviated summer, capitalizing on the greater amount of available moisture. Among them is Sierra primrose, an alpine wildflower preferring moist, rocky soils with reddish blossoms on a 1- to 4-inch stem. There are a limited variety of shrubs, including alpine willow, snow willow, laurel, and heather, in small groupings.
Vegetation grows in small patches in the alpine rock community, unlike the large swaths of foliage in alpine meadows. Open gravel flats and scree areas produce a smattering of alpine plants. The protected microclimates found in boulder fields are oftentimes more suited to the survival of a diverse group of plants; wildflowers are most common, but a few shrubs grow here as well.
Animal Life: Aside from insects and invertebrates, few animals find a permanent home in the rarified alpine zone, where both food and shelter are in short supply. The only common residents are the heather vole, marmot, and pika. Yellow-bellied marmots often sunbathe on the tops of boulders. These usually chubby beasts have brown backs, dull yellow undersides, with white around their eyes and a dark band above their nose. They utter a sharp whistle when alarmed, which accounts for the common name of “whistle pig.”
Sierra bighorn sheep may venture into these heights during the summer, but they generally prefer areas at or below timberline. Similarly, black bears make occasional appearances in the alpine zone but are much more common in the lower elevations. Although many different species of birds frequent the alpine zone, only the rosy finch is as common here as it is in the upper forest zones.
Pinyon-Juniper Woodland
Plant Life: On the east side of the range and in the rain shadow of the Sierra Nevada, between roughly 6,000 and 9,000 feet, is the pinyon-juniper woodland. Typically, this zone receives a mere 5 to 15 inches of precipitation per year, most of which falls as winter snow, with the rest coming from random summer thunderstorms. This zone is composed primarily of widely scattered singleleaf pinyon pine (Pinus monophylla), with Sierra juniper and curl-leaf mountain mahogany as its two most common associates. Trees in this zone often grow in the form of large shrubs, although the pinyon can reach between 20 and 25 feet