Yosemite by John Muir (Illustrated Edition). John Muir
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climate. But that the sequoia can and does grow on as dry ground as any of its present rivals is manifest in a thousand places. "Why, then," it will be asked, "are sequoias always found only in well-watered places?" Simply because a growth of sequoias creates those streams. The thirsty mountaineer knows well that in every sequoia grove he will find running water, but it is a mistake to suppose that the water is the cause of the grove being there; on the contrary, the grove is the cause of the water being there. Drain off the water and the trees will remain, but cut off the trees, and the streams will vanish. Never was cause more completely mistaken for effect than in the case of these related phenomena of sequoia woods and perennial streams.
When attention is called to the method of sequoia stream-making, it will be apprehended at once. The roots of this immense tree fill the ground, forming a thick sponge that absorbs and holds back the rain and melting snow, only allowing it to ooze and flow gently. Indeed, every fallen leaf and rootlet, as well as long clasping root, and prostrate trunk, may be regarded as a dam hoarding the bounty of storm-clouds, and dispensing it as blessings all through the summer, instead of allowing it to go headlong in short-lived floods.
Since, then, it is a fact that thousands of sequoias are growing thriftily on what is termed dry ground, and even clinging like mountain pines to rifts in granite precipices, and since it has also been shown that the extra moisture found in connection with the denser growths is an effect of their presence, instead of a cause of their presence, then the notions as to the former extension of the species and its near approach to extinction, based upon its supposed dependence on greater moisture, are seen to be erroneous.
The decrease in rain and snowfall since the close of the glacial period in the Sierra is much less than is commonly guessed. The highest post-glacial water-marks are well preserved in all the upper river channels, and they are not greatly higher than the spring flood-marks of the present; showing conclusively that no extraordinary decrease has taken place in the volume of the upper tributaries of post-glacial Sierra streams since they came into existence. But, in the meantime, eliminating all this complicated question of climatic change, the plain fact remains that the present rain and snowfall is abundantly sufficient for the luxuriant growth of sequoia forests. Indeed, all my observations tend to show that in a prolonged drought the sugar pines and firs would perish before the sequoia, not alone because of the greater longevity of individual trees, but because the species can endure more drought, and make the most of whatever moisture falls.
Again, if the restriction and irregular distribution of the species be interpreted as a result of the desiccation of the Range, then instead of increasing as it does in individuals toward the south where the rainfall is less, it should diminish. If, then, the peculiar distribution of sequoia has not been governed by superior conditions of soil as to fertility or moisture, by what has it been governed?
In the course of my studies I observed that the northern groves, the only ones I was at first acquainted with, were located on just those portions of the general forest soil-belt that were first laid bare toward the close of the glacial period when the ice-sheet began to break up into individual glaciers. And while searching the wide basin of the San Joaquin, and trying to account for the absence of sequoia where every condition seemed favorable for its growth, it occurred to me that this remarkable gap in the sequoia belt fifty miles wide is located exactly in the basin of the vast, ancient mer de glace of the San Joaquin and Kings River basins which poured its frozen floods to the plain through this gap as its channel. I then perceived that the next great gap in the belt to the northward, forty miles wide, extending between the Calaveras and Tuolumne groves, occurs in the basin of the great ancient mer de glace of the Tuolumne and Stanislaus basins; and that the smaller gap between the Merced and Mariposa groves occurs in the basin of the smaller glacier of the Merced. The wider the ancient glacier, the wider the corresponding gap in the sequoia belt.
Finally, pursuing my investigations across the basins of the Kaweah and Tule, I discovered that the sequoia belt attained its greatest development just where, owing to the topographical peculiarities of the region, the ground had been best protected from the main ice-rivers that continued to pour past from the summit fountains long after the smaller local glaciers had been melted.
Taking now a general view of the belt, beginning at the south we see that the majestic ancient glaciers were shed off right and left down the valleys of Kern and Kings Rivers by the lofty protective spurs outspread embracingly above the warm sequoia-filled basins of the Kaweah and Tule. Then, next northward, occurs the wide sequoia-less channel, or basin of the ancient San Joaquin and sings River mer de glace; then the warm, protected spots of Fresno and Mariposa groves; then the sequoia-less channel of the ancient Merced glacier; next the warm, sheltered ground of the Merced and Tuolumne groves; then the sequoia-less channel of the grand ancient mer de glace of the Tuolumne and Stanislaus; then the warm old ground of the Calaveras and Stanislaus groves. It appears, therefore, that just where, at a certain period in the history of the Sierra, the glaciers were not, there the sequoia is, and just where the glaciers were, there the sequoia is not.
But although all the observed phenomena bearing on the post-glacial history of this colossal tree point to the conclusion that it never was more widely distributed on the Sierra since the close of the glacial epoch; that its present forests are scarcely past prime, if, indeed, they have reached prime; that the post-glacial day of the species is probably not half done; yet, when from a wider outlook the vast antiquity of the genus is considered, and its ancient richness in species and individuals,--comparing our Sierra Giant and Sequoia sempervirens of the Coast Range, the only other living species of sequoia, with the twelve fossil species already discovered and described by Heer and Lesquereux, some of which flourished over vast areas in the Arctic regions and in Europe and our own territories, during tertiary and cretaceous times--then, indeed, it becomes plain that our two surviving species, restricted to narrow belts within the limits of California, are mere remnants of the genus, both as to species and individuals, and that they may be verging to extinction. But the verge of a period beginning in cretaceous times may have a breadth of tens of thousands of years, not to mention the possible existence of conditions calculated to multiply and re-extend both species and individuals.
There is no absolute limit to the existence of any tree. Death is due to accidents, not, as that of animals, to the wearing out of organs. Only the leaves die of old age. Their fall is foretold in their structure; but the leaves are renewed every year, and so also are the essential organs wood, roots, bark, buds. Most of the Sierra trees die of disease, insects, fungi, etc., but nothing hurts the big tree. I never saw one that was sick or showed the slightest sign of decay. Barring accidents, it seems to be immortal. It is a curious fact that all the very old sequoias had lost their heads by lightning strokes. "All things come to him who waits." But of all living things, sequoia is perhaps the only one able to wait long enough to make sure of being struck by lightning.
So far as I am able to see at present only fire and the ax threaten the existence of these noblest of God's trees. In Nature's keeping they are safe, but through the agency of man destruction is making rapid progress, while in the work of protection only a good beginning has been made. The Fresno grove, the Tuolumne, Merced and Mariposa groves are under the protection of the Federal Government in the Yosemite National Park. So are the General Grant and Sequoia National Parks; the latter, established twenty-one years ago, has an area of 240 square miles and is efficiently guarded by a troop of cavalry under the direction of the Secretary of the Interior; so also are the small General Grant National Park, estatblished at the same time with an area of four square miles, and the Mariposa grove, about the same size and the small Merced and Tuolumne group. Perhaps more than half of all the big trees have been thoughtlessly sold and are now in the hands of speculators and mill men. It appears, therefore, that far the largest and important section of protected big trees is in the great Sequoia National Park, now easily accessible by rail to Lemon Cove and thence by a good stage road into the giant forest of the Kaweah and thence by rail to other parts of the park; but large as it is it should be made much larger. Its natural eastern boundary is the High Sierra and the northern and southern boundaries are the Kings and Kern Rivers. Thus could be included the sublime scenery on the headwaters of these rivers and perhaps nine-tenths of all the big trees in existence. All private claims within these bounds should be gradually extinguished by purchase by the Government. The big tree, leaving all its higher uses out of the count,