We come now to the most regularly planted and most clearly defined of the main forest belts, composed almost exclusively of two Silver Firs—Abies concolor and Abies magnifica—extending with but little interruption 450 miles at an elevation of from 5000 to 9000 feet above the sea. In its youth A. concolor is a charmingly symmetrical tree with its flat plumy branches arranged in regular whorls around the whitish-gray axis which terminates in a stout, hopeful shoot, pointing straight to the zenith, like an admonishing finger. The leaves are arranged in two horizontal rows along branchlets that commonly are less than eight years old, forming handsome plumes, pinnated like the fronds of ferns. The cones are grayish-green when ripe, cylindrical, from three to four inches long, and one and a half to two inches wide, and stand upright on the upper horizontal branches. Full-grown trees in favorable situations are usually about 200 feet high and five or six feet in diameter. As old age creeps on, the rough bark becomes rougher and grayer, the branches lose their exact regularity of form, many that are snow-bent are broken off and the axis often becomes double or otherwise irregular from accidents to the terminal bud or shoot. Nevertheless, throughout all the vicissitudes of its three or four centuries of life, come what may, the noble grandeur of this species, however obscured, is never lost.
The magnificent Silver Fir, or California Red Fir (Abies magnifica) is the most symmetrical of all the Sierra giants, far surpassing its companion species in this respect and easily distinguished from it by the purplish-red bark, which is also more closely furrowed than that of the white, and by its larger cones, its more regularly whorled and fronded branches, and its shorter leaves, which grow all around the branches and point upward instead of being arranged in two horizontal rows. The branches are mostly whorled in fives, and stand out from the straight, red-purple bole in level, or in old trees in drooping collars, every branch regularly pinnated like fern-fronds, making broad plumes, singularly rich and sumptuous-looking. The flowers are in their prime about the middle of June; the male red, growing on the underside of the branches in crowded profusion, giving a very rich color to all the trees; the female greenish-yellow, tinged with pink, standing erect on the upper side of the topmost branches, while the tufts of young leaves, about as brightly colored as those of the Douglas spruce, make another grand show. The cones mature in a single season from the flowers. When mature they are about six to eight inches long, three or four in diameter, covered with a fine gray down and streaked and beaded with transparent balsam, very rich and precious-looking, and stand erect like casks on the topmost branches. The inside of the cone is, if possible, still more beautiful. The scales and bracts are tinged with red and the seed-wings are purple with bright iridescence. Both of the silver firs live between two and three centuries when the conditions about them are at all favorable. Some venerable patriarch may be seen heavily storm-marked, towering in severe majesty above the rising generation, with a protecting grove of hopeful saplings pressing close around his feet, each dressed with such loving care that not a leaf seems wanting. Other groups are made up of trees near the prime of life, nicely arranged as if Nature had culled them with discrimination from all the rest of the woods. It is from this tree, called Red Fir by the lumbermen, that mountaineers cut boughs to sleep on when they are so fortunate as to be within its limit. Two or three rows of the sumptuous plushy-fronded branches, overlapping along the middle, and a crescent of smaller plumes mixed to one’s taste with ferns and flowers for a pillow, form the very best bed imaginable. The essence of the pressed leaves seems to fill every pore of one’s body. Falling water makes a soothing hush, while the spaces between the grand spires afford noble openings through which to gaze dreamily into the starry sky. The fir woods are fine sauntering-grounds at almost any time of the year, but finest in autumn when the noble trees are hushed in the hazy light and drip with balsam; and the flying, whirling seeds, escaping from the ripe cones, mottle the air like flocks of butterflies. Even in the richest part of these unrivaled forests where so many noble trees challenge admiration we linger fondly among the colossal firs and extol their beauty again and again, as if no other tree in the world could henceforth claim our love. It is in these woods the great granite domes arise that are so striking and characteristic a feature of the Sierra. Here, too, we find the best of the garden-meadows full of lilies. A dry spot a little way back from the margin of a silver fir lily-garden makes a glorious camp-ground, especially where the slope is toward the east with a view of the distant peaks along the summit of the Range. The tall lilies are brought forward most impressively like visitors by the light of your camp-fire and the nearest of the trees with their whorled branches tower above you like larger lilies and the sky seen through the garden-opening seems one vast meadow of white lily stars.
The Two-Leaved Pine (Pinus contorta, var. Murrayana), above the Silver Fir zone, forms the bulk of the alpine forests up to a height of from 8000 to 9500 feet above the sea, growing in beautiful order on moraines scarcely changed as yet by post-glacial weathering. Compared with the giants of the lower regions this is a small tree, seldom exceeding a height of eighty or ninety feet. The largest I ever measured was ninety feet high and a little over six feet in diameter. The average height of mature trees throughout the entire belt is probably not far from fifty or sixty feet with a diameter of two feet. It is a well-proportioned, rather handsome tree with grayish-brown bark and crooked, much-divided branches which cover the greater part of the trunk, but not so densely as to prevent it being seen. The lower limbs, like those of most other conifers that grow in snowy regions, curve downward, gradually take a horizontal position about half-way up the trunk, then aspire more and more toward the summit. The short, rigid needles in fascicles of two are arranged in comparatively long cylindrical tassels at the ends of the tough up-curving branches. The cones are about two inches long, growing in clusters among the needles without any striking effect except while very young, when the flowers are of a vivid crimson color and the whole tree appears to be dotted with brilliant flowers. The staminate flowers are still more showy on account of their great abundance, often giving a reddish-yellow tinge to the whole mass of foliage and filling the air with pollen. No other pine on the Range is so regularly planted as this one, covering moraines that extend along the sides of the high rocky valleys for miles without interruption. The thin bark is streaked and sprinkled with resin as though it had been showered upon the forest like rain.
Therefore this tree more than any other is subject to destruction by fire. During strong winds extensive forests are destroyed, the flames leaping from tree to tree in continuous belts that go surging and racing onward above the bending wood like prairie-grass fires. During the calm season of Indian summer the fire creeps quietly along the ground, feeding on the needles and cones; arriving at the foot of a tree, the resiny bark is ignited and the heated air ascends in a swift current, increasing in velocity and dragging the flames upward. Then the leaves catch forming an immense column of fire, beautifully spired on the edges and tinted a rose-purple hue. It rushes aloft thirty or forty feet above the top of the tree, forming a grand spectacle, especially at night. It lasts, however, only a few seconds, vanishing with magical rapidity, to be succeeded by others along the fire-line at irregular intervals, tree after tree, upflashing and darting, leaving the trunks and branches scarcely scarred. The heat, however, is sufficient to kill the tree and in a few years the bark shrivels and falls off. Forests miles in extent are thus killed and left standing, with the branches on, but peeled and rigid, appearing gray in the distance like misty clouds. Later the branches drop off, leaving a forest of bleached spars. At length the roots decay and the forlorn gray trunks are blown down during some storm and piled one upon another, encumbering the ground until, dry and seasoned, they are consumed by another fire and leave the ground ready for a fresh crop.
In sheltered lake-hollows, on beds of alluvium, this pine varies so far from the common form that frequently it could be taken for a distinct species, growing in damp sods like grasses from forty to eighty feet high, bending all together to the breeze and whirling in eddying gusts more lively than any other tree in the woods. I frequently found specimens fifty feet high less than five inches in diameter. Being so slender and at the same time clad with leafy boughs, it is often bent and weighed down to the ground when laden with soft snow; thus forming fine ornamental arches, many of them to last until the melting of the snow in the spring.