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Chapter 5
The Trees of the Valley
The most influential of the Valley trees is the yellow pine (Pinus ponderosa). It attains its noblest dimensions on beds of water-washed, coarsely-stratified moraine material, between the talus slopes and meadows, dry on the surface, well-watered below and where not too closely assembled in groves the branches reach nearly to the ground, forming grand spires 200 to 220 feet in height. The largest that I have measured is standing alone almost opposite the Sentinel Rock, or a little to the westward of it. It is a little over eight feet in diameter and about 220 feet high. Climbing these grand trees, especially when they are waving and singing in worship in wind-storms, is a glorious experience. Ascending from the lowest branch to the topmost is like stepping up stairs through a blaze of white light, every needle thrilling and shining as if with religious ecstasy.
Unfortunately there are but few sugar pines in the Valley, though in the King's yosemite they are in glorious abundance. The incense cedar (Libocedrus decurrens) with cinnamon-colored bark and yellow-green foliage is one of the most interesting of the Yosemite trees. Some of them are 150 feet high, from six to ten feet in diameter, and they are never out of sight as you saunter among the yellow pines. Their bright brown shafts and towers of flat, frondlike branches make a striking feature of the landscapes throughout all the seasons. In midwinter, when most of the other trees are asleep, this cedar puts forth its flowers in millions,–the pistillate pale green and inconspicuous, but the staminate bright yellow, tingeing all the branches and making the trees as they stand in the snow look like gigantic goldenrods. The branches, outspread in flat plumes and, beautifully fronded, sweep gracefully downward and outward, except those near the top, which aspire; the lowest, especially in youth and middle age, droop to the ground, overlapping one another, shedding off rain and snow like shingles, and making fine tents for birds and campers. This tree frequently lives more than a thousand years and is well worthy its place beside the great pines and the Douglas spruce.
The two largest specimens I know of the Douglas spruce, about eight feet in diameter, are growing at the foot of the Liberty Cap near the Nevada Fall, and on the terminal moraine of the small residual glacier that lingered in the shady Illilouette Cañon.
After the conifers, the most important of the Yosemite trees are the oaks, two species; the California live-oak (Quercus agrifolia), with black trunks, reaching a thickness of from four to nearly seven feet, wide spreading branches and bright deeply-scalloped leaves. It occupies the greater part of the broad sandy flats of the upper end of the Valley, and is the species that yields the acorns so highly prized by the Indians and woodpeckers.
The other species is the mountain live-oak, or goldcup oak (Quercus chrysolepis), a sturdy mountaineer of a tree, growing mostly on the earthquake taluses and benches of the sunny north wall of the Valley. In tough, unwedgeable, knotty strength, it is the oak of oaks, a magnificent tree.
The largest and most picturesque specimen in the Valley is near the foot of the Tenaya Fall, a romantic spot seldom seen on account of the rough trouble of getting to it. It is planted on three huge boulders and yet manages to draw sufficient moisture and food from this craggy soil to maintain itself in good health. It is twenty feet in circumference, measured above a large branch between three and four feet in diameter that has been broken off. The main knotty trunk seems to be made up of craggy granite boulders like those on which it stands, being about the same color as the mossy, lichened boulders and about as rough. Two moss-lined caves near the ground open back into the trunk, one on the north side, the other on the west, forming picturesque, romantic seats. The largest of the main branches is eighteen feet and nine inches in circumference, and some of the long pendulous branchlets droop over the stream at the foot of the fall where it is gray with spray. The leaves are glossy yellow-green, ever in motion from the wind from the fall. It is a fine place to dream in, with falls, cascades, cool rocks lined with hypnum three inches thick; shaded with maple, dogwood, alder, willow; grand clumps of lady-ferns where no hand may touch them; light filtering through translucent leaves; oaks fifty feet high; lilies eight feet high in a filled lake basin near by, and the finest libocedrus groves and tallest ferns and goldenrods.
In the main river cañon below the Vernal Fall and on the shady south side of the Valley there are a few groves of the silver fir (Abies concolor), and superb forests of the magnificent species round the rim of the Valley.
On the tops of the domes is found the sturdy, storm-enduring red cedar (Juniperus occidentalis). It never makes anything like a forest here, but stands out separate and independent in the wind, clinging by slight joints to the rock, with scarce a handful of soil in sight of it, seeming to depend chiefly on snow and air for nourishment, and yet it has maintained tough health on this diet for two thousand years or more. The largest hereabouts are from five to six feet in diameter and fifty feet in height.
The principal river-side trees are poplar, alder, willow, broad-leaved maple, and Nuttall's flowering dogwood. The poplar (Populus trichocarpa), often called balm-of-Gilead from the gum on its buds, is a tall tree, towering above its companions and gracefully embowering the banks of the river. Its abundant foliage turns bright yellow in the fall, and the Indian-summer sunshine sifts through it in delightful tones over the slow-gliding waters when they are at their lowest ebb.
Some of the involucres of the flowering dogwood measure six to eight inches in diameter, and the whole tree when in flower looks as if covered with snow. In the spring when the streams are in flood it is the whitest of trees. In Indian summer the leaves become bright crimson, making a still grander show than the flowers.
The broad-leaved maple and mountain maple are found mostly in the cool cañons at the head of the Valley, spreading their branches in beautiful arches over the foaming streams.
Scattered here and there are a few other trees, mostly small–the mountain mahogany, cherry, chestnut-oak, and laurel. The California nutmeg (Torreya californica), a handsome evergreen belonging to the yew family, forms small groves near the cascades a mile or two below the foot of the Valley.
Chapter 6
The Forest Trees in General
For the use of the ever-increasing number of Yosemite visitors who make extensive excursions into the mountains beyond the Valley, a sketch of the forest trees in general will probably be found useful. The different species are arranged in zones and sections, which brings the forest as a whole within the comprehension of every observer. These species are always found as controlled by the climates of different elevations, by soil and by the comparative strength of each species in taking and holding possession of the ground; and so appreciable are these relations the traveler need never be at a loss in determining within a few hundred feet his elevation above sea level by the trees alone; for, notwithstanding some of the species range upward for several thousand feet and all pass one another more or less, yet even those species possessing the greatest vertical range are available in measuring the elevation; inasmuch as they take on new forms corresponding with variations in altitude. Entering the lower fringe of the forest composed of Douglas oaks and Sabine pines, the trees grow so far apart that not one-twentieth of the surface of the ground is in shade at noon. After advancing fifteen or twenty miles towards Yosemite and making an ascent of from two to three thousand feet you reach the lower margin of the main pine belt, composed of great sugar pine, yellow pine, incense cedar and sequoia. Next you come to the magnificent silver-fir belt and lastly to the upper pine belt, which sweep up to the feet of the summit peaks in a dwarfed fringe, to a height of from ten to twelve thousand feet. That this general order of distribution depends on climate as affected by height above the sea, is seen at once, but there are other harmonies that become manifest only after observation and study. One of the most interesting of these is the arrangement of the forest in long curving bands, braided together into lace-like patterns in some places and out-spread in charming variety. The key to these striking arrangements is the system of ancient glaciers; where they flowed the trees followed, tracing their courses along the sides of cañons, over ridges, and high plateaus. The cedar of Lebanon, said Sir Joseph Hooker, occurs upon one of the moraines of an ancient glacier. All the forests of the Sierra are growing upon moraines, but moraines vanish like the glaciers that make them. Every storm that falls upon them wastes them, carrying away their decaying, disintegrating material into new formations, until they are no longer recognizable without tracing their transitional forms down the Range from those still in process of formation in some places through those that are more and more ancient and more obscured by vegetation and all kinds of post-glacial weathering. It appears, therefore, that the Sierra forests indicate the extent and positions of ancient moraines as well as they do belts of climate.
One will have no difficulty in knowing the Nut Pine (Pinus Sabiniana), for it is the first conifer met in ascending the Range from the west, springing up here and there among Douglas oaks and thickets of ceanothus and manzanita; its extreme upper limit being about 4000 feet above the sea, its lower about from 500 to 800 feet. It is remarkable for its loose, airy, wide-branching habit and thin gray foliage. Full-grown specimens are from forty to fifty feet in height and from two to three feet in diameter. The trunk usually divides into three or four main branches about fifteen or twenty feet from the ground that, after bearing away from one another, shoot straight up and form separate summits. Their slender, grayish needles are from eight to twelve inches long, and inclined to droop, contrasting with the rigid, dark-colored trunk and branches. No other tree of my acquaintance so substantial in its body has foliage so thin and pervious to the light. The cones are from five to eight inches long and about as large in thickness; rich chocolate-brown in color and protected by strong, down-curving nooks which terminate the scales. Nevertheless the little Douglas Squirrel can open them. Indians climb the trees like bears and beat off the cones or recklessly cut off the more fruitful branches with hatchets, while the squaws gather and roast them until the scales open sufficiently to allow the hard-shell seeds to be beaten out. The curious little Pinus attenuata is found at an elevation of from 1500 to 3000 feet, growing in close groves and belts. It is exceedingly slender and graceful, although trees that chance to stand alone send out very long, curved branches, making a striking contrast to the ordinary grove form. The foliage is of the same peculiar gray-green color as that of the nut pine, and is worn about as loosely, so that the body of the tree is scarcely obscured by it. At the age of seven or eight years it begins to bear cones in whorls on the main axis, and as they never fall off, the trunk is soon picturesquely dotted with them. Branches also soon become fruitful. The average size of the tree is about thirty or forty feet in height and twelve to fourteen inches in diameter. The cones are about four inches long and covered with a sort of varnish and gum, rendering them impervious to moisture.
No observer can fail to notice the admirable adaptation of this curious pine to the fire-swept regions where alone it is found. After a running fire has scorched and killed it the cones open and the ground beneath it is then sown broadcast with all the seeds ripened during its whole life. Then up spring a crowd of bright, hopeful seedlings, giving beauty for ashes in lavish abundance.
The Sugar Pine, King Of Pine Trees
Of all the world's eighty or ninety species of pine trees, the Sugar Pine (Pinus Lambertiana) is king, surpassing all others, not merely in size but in lordly beauty and majesty. In the Yosemite region it grows at an elevation of from 3000 to 7000 feet above the sea and attains most perfect development at a height of about 5000 feet. The largest specimens are commonly about 220 feet high and from six to eight feet in diameter four feet from the ground, though some grand old patriarch may be met here and there that has enjoyed six or eight centuries of storms and attained a thickness of ten or even twelve feet, still sweet and fresh in every fiber. The trunk is a remarkably smooth, round, delicately-tapered shaft, straight and regular as if turned in a lathe, mostly without limbs, purplish brown in color and usually enlivened with tufts of a yellow lichen. Toward the head of this magnificent column long branches sweep gracefully outward and downward, sometimes forming a palm-like crown, but far more impressive than any palm crown I ever beheld. The needles are about three inches long in fascicles of five, and arranged in rather close tassels at the ends of slender branchlets that clothe the long outsweeping limbs. How well they sing in the wind, and how strikingly harmonious an effect is made by the long cylindrical cones, depending loosely from the ends of the long branches! The cones are about fifteen to eighteen inches long, and three in diameter; green, shaded with dark purple on their sunward sides. They are ripe in September and October of the second year from the flower. Then the flat, thin scales open and the seeds take wing, but the empty cones become still more beautiful and effective as decorations, for their diameter is nearly doubled by the spreading of the scales, and their color changes to yellowish brown while they remain, swinging on the tree all the following winter and summer, and continue effectively beautiful even on the ground many years after they fall. The wood is deliciously fragrant, fine in grain and texture and creamy yellow, as if formed of condensed sunbeams. The sugar from which the common name is derived is, I think, the best of sweets. It exudes from the heart-wood where wounds have been made by forest fires or the ax, and forms irregular, crisp, candy-like kernels of considerable size, something like clusters of resin beads. When fresh it is white, but because most of the wounds on which it is found have been made by fire the sap is stained and the hardened sugar becomes brown. Indians are fond of it, but on account of its laxative properties only small quantities may be eaten. No tree lover will ever forget his first meeting with the sugar pine. In most pine trees there is the sameness of expression which to most people is apt to become monotonous, for the typical spiral form of conifers, however beautiful, affords little scope for appreciable individual character. The sugar pine is as free from conventionalities as the most picturesque oaks. No two are alike, and though they toss out their immense arms in what might seem extravagant gestures they never lose their expression of serene majesty. They are the priests of pines and seem ever to be addressing the surrounding forest. The yellow pine is found growing with them on warm hillsides, and the silver fir on cool northern slopes but, noble as these are, the sugar pine is easily king, and spreads his arms above them in blessing while they rock and wave in sign of recognition. The main branches are sometimes forty feet long, yet persistently simple, seldom dividing at all, excepting near the end; but anything like a bare cable appearance is prevented by the small, tasseled branchlets that extend all around them; and when these superb limbs sweep out symmetrically on all sides, a crown sixty or seventy feet wide is formed, which, gracefully poised on the summit of the noble shaft, is a glorious object. Commonly, however, there is a preponderance of limbs toward the east, away from the direction of the prevailing winds.
Although so unconventional when full-grown, the sugar pine is a remarkably proper tree in youth–a strict follower of coniferous fashions–slim, erect, with leafy branches kept exactly in place, each tapering in outline and terminating in a spiry point. The successive forms between the cautious neatness of youth and the bold freedom of maturity offer a delightful study. At the age of fifty or sixty years, the shy, fashionable form begins to be broken up. Specialized branches push out and bend with the great cones, giving individual character, that becomes more marked from year to year. Its most constant companion is the yellow pine. The Douglas spruce, libocedrus, sequoia, and the silver fir are also more or less associated with it; but on many deep-soiled mountain-sides, at an elevation of about 5000 feet above the sea, it forms the bulk of the forest, filling every swell and hollow and down-plunging ravine. The majestic crowns, approaching each other in bold curves, make a glorious canopy through which the tempered sunbeams pour, silvering the needles, and gilding the massive boles and the flowery, park-like ground into a scene of enchantment. On the most sunny slopes the white-flowered, fragrant chamaebatia is spread like a carpet, brightened during early summer with the crimson sarcodes, the wild rose, and innumerable violets and gilias. Not even in the shadiest nooks will you find any rank, untidy weeds or unwholesome darkness. In the north sides of ridges the boles are more slender, and the ground is mostly occupied by an underbrush of hazel, ceanothus, and flowering dogwood, but not so densely as to prevent the traveler from sauntering where he will; while the crowning branches are never impenetrable to the rays of the sun, and never so interblended as to lose their individuality.
The Yellow Or Silver Pine
The Silver Pine (Pinus ponderosa), or Yellow Pine, as it is commonly called, ranks second among the pines of the Sierra as a lumber tree, and almost rivals the sugar pine in stature and nobleness of port. Because of its superior powers of enduring variations of climate and soil, it has a more extensive range than any other conifer growing on the Sierra. On the western slope it is first met at an elevation of about 2000 feet, and extends nearly to the upper limit of the timber-line. Thence, crossing the range by the lowest passes, it descends to the eastern base, and pushes out for a considerable distance into the hot, volcanic plains, growing bravely upon well-watered moraines, gravelly lake basins, climbing old volcanoes and dropping ripe cones among ashes and cinders.
The average size of full-grown trees on the western slope where it is associated with the sugar pine, is a little less than 200 feet in height and from five to six feet in diameter, though specimens considerably larger may easily be found. Where there is plenty of free sunshine and other conditions are favorable, it presents a striking contrast in form to the sugar pine, being a symmetrical spire, formed of a straight round trunk, clad with innumerable branches that are divided over and over again. Unlike the Yosemite form about one-half of the trunk is commonly branchless, but where it grows at all close three-fourths or more is naked, presenting then a more slender and elegant shaft than any other tree in the woods. The bark is mostly arranged in massive plates, some of them measuring four or five feet in length by eighteen inches in width, with a thickness of three or four inches, forming a quite marked and distinguishing feature. The needles are of a fine, warm, yellow-green color, six to eight inches long, firm and elastic, and crowded in handsome, radiant tassels on the upturning ends of the branches. The cones are about three or four inches long, and two and a half wide, growing in close, sessile clusters among the leaves.
The species attains its noblest form in filled-up lake basins, especially in those of the older yosemites, and as we have seen, so prominent a part does it form of their groves that it may well be called the Yosemite Pine.
The Jeffrey variety attains its finest development in the northern portion of the Range, in the wide basins of the McCloud and Pitt Rivers, where it forms magnificent forests scarcely invaded by any other tree. It differs from the ordinary form in size, being only about half as tall, in its redder and more closely-furrowed bark grayish-green foliage, less divided branches, and much larger cones; but intermediate forms come in which make a clear separation impossible, although some botanists regard it as a distinct species. It is this variety of ponderosa that climbs storm-swept ridges alone, and wanders out among the volcanoes of the Great Basin. Whether exposed to extremes of heat or cold, it is dwarfed like many other trees, and becomes all knots and angles, wholly unlike the majestic forms we have been sketching. Old specimens, bearing cones about as big as pineapples, may sometimes be found clinging to rifted rocks at an elevation of 7000 or 8000 feet, whose highest branches scarce reach above one's shoulders.
I have often feasted on the beauty of these noble trees when they were towering in all their winter grandeur, laden with snow–one mass of bloom; in summer, too, when the brown, staminate clusters hang thick among the shimmering needles, and the big purple burrs are ripening in the mellow light; but it is during cloudless wind-storms that these colossal pines are most impressively beautiful. Then they bow like willows, their leaves streaming forward all in one direction, and, when the sun shines upon them at the required angle, entire groves glow as if every leaf were burnished silver. The fall of tropic light on the crown of a palm is a truly glorious spectacle, the fervid sun-flood breaking upon the glossy leaves in long lance-rays, like mountain water among boulders at the foot of an enthusiastic cataract. But to me there is something more impressive in the fall of light upon these noble, silver pine pillars: it is beaten to the finest dust and shed off in myriads of minute sparkles that seem to radiate from the very heart of the tree as if like rain, falling upon fertile soil, it had been absorbed to reappear in flowers of light. This species also gives forth the finest wind music. After listening to it in all kinds of winds, night and day, season after season, I think I could approximate to my position on the mountain by this pine music alone. If you would catch the tone of separate needles climb a tree in breezy weather. Every needle is carefully tempered and gives forth no uncertain sound each standing out with no interference excepting during head gales; then you may detect the click of one needle upon another, readily distinguishable from the free wind-like hum.
When a sugar pine and one of this species equal in size are observed together, the latter is seen to be more simple in manners, more lively and graceful, and its beauty is of a kind more easily appreciated; on the other hand it is less dignified and original in demeanor. The yellow pine seems ever eager to shoot aloft, higher and higher. Even while it is drowsing in autumn sun-gold you may still detect a skyward aspiration, but the sugar pine seems too unconsciously noble and too complete in every way to leave room for even a heavenward care.
