FOREST TYPES.1
The forests of the Mount Rainier National Park contain few deciduous trees, but are remarkable for the variety and beauty of their conifers. The distribution of species and their mode of growth, the size of the trees, and the density of the stand are determined, primarily, by the altitude. The dense evergreen forests characteristic of the lower western slopes of the Cascades extend into the park in the valleys of the main and West Fork of White River, the Carbon, the Mowich, the Nisqually, and the Ohanapecosh. Favored by the warm and equable temperatures and the moist, well-drained soil of the river bottoms and protected from the wind by the inclosing ridges, the trees are perfectly proportioned and grow to a great height. The forest is of all ages from the seedling concealed in the undergrowth to the veteran 4 to 8 feet in diameter and perhaps 400 years old. The average increase at the stump in valley land is about 1 inch in six years. A Douglas fir growing along the stage road between the park boundary and Longmire's, at the age of 90 to 120 years, may have a breast diameter of 20 inches and yield 700 feet of saw timber. But many of the trees of this size may be much older on account of having grown in the shade or under other adverse conditions. The trees between 200 and 300 years of age are often 40 to 50 inches in diameter and may yield an average of from 2,700 to 5,500 board feet. The largest Douglas firs are sometimes over 400 years old and 60 to 70 inches in diameter. Such trees when sound will produce over 8,000 feet of lumber. Up to 3,000 feet the forests about Mount Rainier are composed of species common throughout the western parts of British Columbia, Washington, Oregon, and northern California. The dominant trees are the western hemlock and the Douglas fir. While these trees compose the type peculiar to the bottom lands, they are not confined to it, but extend to the ridges and continue to be the prevailing species up to 3,000 feet. The stand on the mountain slopes is lighter and more open, and the trees are smaller. Huckleberry bushes and other shrubs adapted to the drier soil of the foothills, Oregon grape, and salal take the place of the tall and dense undergrowth of the bottom lands, and the amount of fallen timber is noticeably less. Between the elevations of 3,000 and 4,500 feet the general character of the forest is intermediate between that of the lowland type and the subalpine growth of the high mountains. The forest is continuous, except where broken by extremely steep slopes and rocky crests where sufficient soil has not accumulated to support arborescent growth. In general, there is little undergrowth. The stand is fairly close on flats, benches, and moderate slopes and more open on exposed situations and wind-swept ridges. The prevailing trees are the amabilis and noble fir. They so grow separately in pure stands, but more often are associated. At the lower limits of this type they are mixed with the Douglas fir and hemlock, while subalpine species appear at the upper limits. A large part of the area above the 4,500-foot contour consists of open, grassy parks, rocky and barren summits, snow fields, and glaciers. Tracts of dense subalpine forest occur in sheltered locations, but they are nowhere very extensive, and their continuity is broken by open swamp glades and meadows and small bodies of standing water. The steep upper slopes of the spurs diverging from the main ridges are frequently covered with a stunted, scraggy growth of low trees firmly rooted in the crevices between the rocks. The most beautiful of the alpine trees are about the mountain parks. Growing in scattered groves and standing in groups or singly in the open grassland and on the margins of the lakes, they produce a peculiarly pleasing landscape effect which agreeably relieves the traveler from the extended outlook to the snow fields of the mountain and broken ridges about it. At the lower levels of the subalpine forest the average height of the largest trees is from 50 to 60 feet. The size diminishes rapidly as the elevation increases. The trees are dwarfed by the cold, and their trunks are bent and twisted by the wind. Small patches of low, weather-beaten, and stunted mountain hemlock, alpine fir, and white-bark pine occur up to 7,000 feet. A few diminutive mountain hemlock grow above this elevation. The trunks are quite prostrate, and the crowns are flattened mats of branches lying close to the ground. The extreme limit of tree growth on Mount Rainier is about 7,600 feet. There is no distinct timberline. Notwithstanding the shortness of the summer season at high altitudes, the subalpine forests in some parts of the park have suffered severely from fire. There has been little apparent change in the alpine burns within the last 30 years. Reforestation at high altitudes is extremely slow. The seed production is rather scanty, and the ground conditions are not favorable for its reproduction It will take more than one century for nature to replace the beautiful groves which have been destroyed by the carelessness of the first visitors to the mountain. At low elevations the forest recovers more rapidly from the effects of fire. Between the subalpine areas and the river valleys there are several large, ancient burns which are partly reforested. The most extensive of these tracts is the Muddy Fork Burn. It is crossed by the Stevens Canyon Trail from Reflection Likes to the Ohanapecosh Hot Springs. This burn includes an area of 20 square miles in the park and extends north nearly to the glaciers and south for several miles beyond the park boundary nearly to the main Cowlitz River. The open sunlit spaces and wide outlooks afforded by reforested tracts of this character present a strong contrast to the deep shades and dim vistas of the primitive forest. On the whole, they have a cheerful and pleasing appearance very diferent from the sad, desolate aspect of the alpine burns, which less kindly conditions of climate and exposure have kept from reforestation.
The flowering plants in the forest in the zone ranging from 2,000 feet to 4,000 feet are those adapted to grow in the shade. Many of these live on decayed vegetation instead of preparing their own food as ordinary plants do under the action of light on the green coloring matter in their leaves. Some of these so-called flowering plants have in reality become fungi, depending wholly on other plants for their food. Two forms of the ghost plant or Indian pipe are good examples of these colorless forms. In addition to these saprophytic plants there are many others providing their own living, such as the Indian pipsissewa, the pyrolas, and the moneses, producing beautiful waxy flowers. Nearly everywhere through the moss grows the little bunchberry or Canada dogwood. Close companions of the latter are the forest anemone, the ovate trillium, and the beautiful white, one-flowered clintonia. The sword fern, deer fern, oak fern, lady fern, and maidenhair fern all vie with each other in producing a beautiful setting among those giant trees and graceful flowering plants. Many trails wind through these enchanted woods, giving the tourist an opportunity to forget the cares of business life and see nature at its best. In the upper area of this zone the squaw grass, mertens, corral root, the racemose pedicularis, the secund pyrola, and the ovate salal are typical plants. Here and there along the roadside the beautiful twin flower hangs down gracefully over the embankments, filling the air with its fragrance. This can be seen along the road long before the park is reached, though at its best between 2,000 and 3,000 feet elevation. At about 4,000 feet the glacial valleys make openings into the forest. In the open places the plants of the higher regions often blend with those of the forest areas. In many places the sinuate mountain alder, the devil's club, and the salmonberry form dense jungles. The spring beauties, pentstemons, monkey flowers, luinas, stonecrops, and mertensias are common on the old moraines and moist places. The forest continues up to 4,500 feet, at which elevation the grassy meadows begin. Here begins also the real floral beauty of the park. The lower meadows are generally moist and often swampy. The typical plants are the cotton grass, spiraeas, asters, erythroniums, arnicas, monkey flowers, the creamy firewood, swamp speedwells, sedges, and willows. These moist meadows soon give way to dry grassy areas interspersed with beautiful symmetrical tree groups. As elevation increases the groups of trees diminish in both number and size until timber line is reached, when they form prostrate mats at about 6,700 feet. The region of the greatest floral beauty is about 5,400 feet. Here the plants are large, growing in fertile soil. Here the color of the leaves as well as the floral organs are superb. All colors are represented. The principal plants having red flowers in this zone are Indian paint brush, Lewis's monkey flower, red heather, rosy spiraea, and the fireweeds; those having white flowers are valerians, mountain dock, saxifrages, avalanche lilies, several umbelliferous plants, and the cudweeds; those having blue flowers are speedwells, lupines, mertensias, pentstemons, and violets; those having yellow flowers are the arnicas, potentillas, buttercups, deertongues, stonecrops, mountain dandelions, and monkey flowers. The principal plants in the pumice fields above timber line are the mountain phlox, golden aster, Lyall's lupine, yellow heather, scarlet pentstemon, hulsea nana, purple phaclia, golden draba, and smelowskia. The last two vie with each other for attaining the highest altitude.
1920/mora/sec2.htm Last Updated: 16-Feb-2010 |