Among the blossoms that shine in these polar gardens are the spring beauty, the daisy, the b.u.t.tercup, and the forget-me-not. There are numbers of the pink and the saxifrage families, white and purple monkshood, purple asters, and goldenrod. Whole slopes are covered with paintbrushes, and among these commonly is a scattering of tall, white-tipped wild buckwheat. Some of these are scentless, while others diffuse a rich perfume.
There are numerous hanging gardens that are grander than all the kings of the earth could create! White cascades with the soft, fluttering veils of spray pour through the brilliant bloom and the bright green of the terraces. In these gardens may bloom the bluest of mertensia, gentians, and polemonium, the brightest of yellow avens, the ruddy stonecrop, and gaillardias as handsome as any black-eyed Susan; then there is a fine scattering of shooting-stars, starworts, pentstemons of prettiest shades, and the tall and stately columbine, a burst of silver and blue.
Many of the polar plants that bloom in this Arctic world were probably brought here from the Arctic Circle by the vast and prolonged flow of ice from the north during the last ice age. Stranded here by the receding, melting ice, they are growing up with the country under conditions similar to those in the Northland. They are quick to seize and beautify each new soil-bed that appears,--soil exposed by the shrinking of snow-fields, piled by landslides, washed down by water, or made by the dropped or deposited sweepings of the winds.
Bees and b.u.t.terflies follow the flowers, and every wild garden has the buzz of busy wings and the painted sails of idle ones. Mountain sheep occasionally pose and group among the flowers and b.u.t.terflies. Often sheep, crags, ptarmigan, and green s.p.a.ces, flowers, and waterfalls are caught in one small s.p.a.ce that sweeps up into the blue and cloud in one grand picture.
In many localities there are such numbers of dwarfed plants that one may blunder through a fairy flower-garden without seeing it. To see these tiny flowers at their best, one needs to lie down and use a reading-gla.s.s. There are diminutive bellflowers that rise only half an inch above the earth and ma.s.ses of cushion pinks and tiny phlox still finer and shorter.
The Arctic-Alpine zone, with its cloud and bright sunshine, rests upon the elevated and broken world of the Rockies. This realm is full of interest through all the seasons, and with its magnificence are lovely places, brilliant flowers, and merry birds to cheer its solitudes.
During winter these polar mountain-stretches have a strange charm, and many a time my snowshoe tracks have left dotted trails upon their snowy distances.
These cheerful wild gardens are threatened with ruin. Cattle and sheep are invading them farther and farther, and leaving ruin behind. With their steep slopes, coa.r.s.e soil, and shallow root-growths these alpine growths cannot endure pasturage. The biting, the pulling, and the choppy hoof-action are ruinous. Destined to early ruin if pastured, and having but little value when so used, these sky gardens might rightly be kept unimpaired for ourselves. They would make delightful National Parks. They have a rapidly increasing value for parks. Used for recreation places, they would have a high commercial value; and thus used they would steadily pay dividends in humanity.
Some Forest History
Some Forest History
Two picturesque pine stumps stood for years in the edge of a grove near my cabin. They looked as old as the hills. Although they had wasted a little through weathering, they showed no sign of decay.
Probably they were the ruins of yellow pine trees that before my day had perished in a forest fire. The heat of the fire that had caused their death had boiled the pores of these stumps full of pitch. They were thus preserved, and would endure a long, long time.
I often wondered how old they were. A chance to get this information came one morning when a number of old pines that grew around these stumps were blown over. Among those that went down were three large and ancient yellow pines and several smaller lodge-pole pines. These I dissected and studied, with the idea that their annual wood rings, together with the scars and embossments, might give information concerning the death of the old brown-gray stumps.
Two of the yellow pines showed two hundred and fifty-six annual rings; the other showed two hundred and fifty-five. All carried fire scars, received in the year 1781. Apparently, then, the stumps had been dead and weathering since 1781. The annual rings in the overthrown lodge-poles showed that they started to grow in 1782. Lodge-pole pines commonly spring up immediately after a fire; these had apparently taken possession of the ground as soon as it was laid bare by the fire that had killed and partly consumed the two yellow pines and injured the three scarred ones. Since the lodge-poles were free from fire scars, since the yellow pine showed no scar after 1781, and since all these trees had stood close about the stumps, it was plain that the stumps were the remnants of trees that perished in a forest fire in 1781.
Later, a number of trees elsewhere in the grove were called upon to testify, and these told a story that agreed with that of the trees that had stood close to the stumps. These stumps are now the newel-posts in a rustic stairway.
[Ill.u.s.tration: A WESTERN YELLOW PINE]
Near my home on the slope of Long"s Peak are the records of an extraordinary succession of forest fires. During the last two hundred and fifty years eight large fires and numerous small ones have occurred. Each left a black, fire-engraved date-mark. The dates of some of these fires are 1675, 1707, 1753, 1781, 1842, 1864, 1878, 1885, and 1900. Each fire burned over from a few hundred to a few thousand acres. In part, nature promptly reforested after each fire; consequently some of the later fires swept over areas that had been burned over by the earlier ones. Here and there a fire-scarred tree, escaping with its life, lived on to preserve in its rings the date of the conflagration. In one old pine I found seven widely separated scars that told of seven different fires. In addition to the records in isolated trees, there were records also in many injured trees in groves that had survived and in ragged forest-edges where forest fires had stopped. An excellent check on the evidence given by the annual rings of fire-scarred trees was found in the age of the new tree-growth that came up in the fire-swept territory in which, or on the borders of which, were the telltale fire-injured trees.
Some fires swept so clean that they left behind no date of their ravages, but here and there the character of the forest and of the soil in which it stood made me feel certain that the growth had arisen from the ashes of a fire, and that I could tell the extent of the fire. In most localities the fire-killed forest is at once restored by nature. That ever enthusiastic sower, the wind, reseeds most burned areas within a year. Burns on the Western mountains commonly are covered with young lodge-pole or aspen within three years. There are a few dry wind-swept slopes or places left rocky for which years or even centuries may be required to re-earth and reforest.
Some members of the Pine Family endure fire much better than others.
The "big tree," the redwood, and the yellow and sugar pines will survive far hotter fires than their relatives, for their vitals are protected by a thick sheath of slow-burning bark. The Western yellow pine is one of the best fire-fighters in the forest world. Its vitals appear able to endure unusual heat without death, and it will survive fires that kill neighboring trees of other kinds. In old trees the trunk and large limbs are thickly covered with heat-and-fire-resisting bark. In examining a number of these old fellows that were at last laid low by snow or landslide or the axe, I found that some had triumphantly survived a number of fiery ordeals and two or three lightning-strokes. One pine of eight centuries carried the scars of four thunderbolts and seven wounds that were received from fires decades apart.
The deciduous, or broad-leaf, trees resist fires better than the coniferous, or evergreen, trees. Pines and spruces take fire much more readily than oaks and maples, because of the resinous sap that circulates through them; moreover, the pines and spruces when heated give off an inflammable gas which, rising in front of a forest fire, adds to the heat and destructiveness, and the eagerness of the blaze.
Considered in relation to a fire, the coniferous forest is a poor risk because it is more inflammable than a deciduous one.
Another advantage possessed by broad-leaf trees lies in the rapid growth of their seedlings. Surface fires annihilate most tiny trees.
Two-year-old chestnuts, maples, and, in fact, many of the broad-leaf youngsters, are three or more feet high, and are able to survive a severe fire; but two-year-old white pine, Engelmann spruce, or long-leaf pine are barely two inches high,--just fuzzy-topped matches stuck in the earth that perish in a flash from a single breath of flame.
The ability to send up sprouts, which most deciduous trees possess, is also a very great advantage in the fight against fire. A fire may destroy a deciduous forest and all its seeds without injuring the potent roots beneath the surface. The year following the fire, most of these roots send up sprouts that swiftly grow to replace the fallen forest. Among the so-called Pine Family, the ability to send up sprouts or shoots is limited to a few kinds, most prominent of which is the redwood.
Repeated forest fires have injured enormously the Southern hardwood forests; they have damaged millions of trees so that they have become hollow or punky-hearted. These fires have burned off limbs or burned into the trunks or the roots and made openings through which many kinds of fungi have entered the hearts of the trees, to doom them to rot and decay.
Forest fires have been common through the ages. Charcoal has been found in fossil. This has a possible age of a million years. Charred logs have been found, in Dakota and elsewhere, several hundred feet beneath the surface. The big trees of California have fire scars that are two thousand years old.
The most remarkable forest fire records that I ever saw were found in a giant California redwood. This tree was felled a few years ago. Its trunk was cut to pieces and studied by scientific men, who from the number of its annual rings found the year of its birth, and also deciphered the dates of the various experiences the tree had had with fire.
This patriarch had stood three hundred feet high, was sound to the core, and had lived through two thousand one hundred and seventy-one years. Its existence began in the year 271 B.C. After more than five centuries of life, in A.D. 245 it was in the pathway of a forest fire from which it received a bad burn on the lower trunk. It was one hundred and five years before this burn was fully covered with tissue and bark.
Following this fire came the peaceful procession of twelve centuries.
Eleven hundred and ninety-six times the golden poppies came to glorify the green hills of spring, while the songs of mating birds filled woods and meadows. More than a thousand times the aspens ripened and scattered their golden leaves, while this serene evergreen grew and towered more and more n.o.ble through the centuries.
Elsewhere the forests were dim with smoke, and on the Sierra during these centuries the heroic "big trees" received many a scar from fire.
But not until 1441 did fire again try this veteran. Soon after this burn was healed there came a third fire. This was less injurious than the preceding ones, for the wound that it inflicted healed in half a century.
Higher and more stately the tree grew, and in 1729 it attained the age of two thousand years. At the age of two thousand and eighty-eight years the fourth fire attacked it. This fire burned an eighteen-foot scar upon the trunk of the old tree. In 1900, after the lapse of almost a century, only a small part of this wound was overgrown. This year, 1900, came the reaper, the axeman, who laid low this aged and monumental tree!
What starts forest fires? Some are started by lightning; others are kindled by meteors that are flung from the sky, or by fire that is hurled or poured from a volcano; a few are caused by spontaneous combustion; and many are set by man. Down through the ages primitive and civilized men have frequently set fire to the forest. These fires are set sometimes accidentally, sometimes intentionally. The forest has been fired to drive out game, to improve pasturage, to bewilder the enemy during war, and to clear the land for the plow.
During one of my Colorado camping-trips a high October wind brought me the information that spruce wood was burning near by. While I was searching for the fire in the thick needle carpet of the forest floor, a spark from above settled before me. A fire was sputtering and starting in a tree top about thirty feet above the earth. This fire was starting where a dead leaning tree-trunk was rasping and rubbing against an upright one. The bark of the standing tree was powdered and tufted with wood-dust which had been ground by friction from the trunks as they swayed and rotated in the wind. This inflammable wood-dust, together with acc.u.mulated bark-bits and needles, had been set on fire from the heat generated by these two big sticks rubbing together. Plainly this was a friction fire. The incessant swaying of treetops in the tireless wind occasionally causes a smoke from friction at points where overlapping limbs or entangled trees are rubbing. Within a few minutes after my discovery, this fire was roaring eagerly through the treetops.
Friction fires are rare, but my old notebooks tell of numerous fires that were set by lightning. Before this fire, which was in the Sangre de Cristo Mountains, had died out, a lightning-set fire in the mountains of central Colorado had attracted my attention with ma.s.sive, magnificent smoke-clouds, which were two or three thousand feet above the mountain-tops. Though thirty miles distant, these clouds occasionally took on the bossy white splendor of big c.u.muli a.s.sembling for summer rain. I resolved to see the fire at close range.
Until burned territory was reached, I followed along sky-line ridges through changing conditions of clear sky, smoke, and falling ashes, ready for swift retreat down a slope in case the fire advanced under smoke cover and surprised me. The burn was entered at the first edge I reached. Millions of seared and blackened trees were standing steadfastly where they had died at their post. All twigs and leaf.a.ge were burned away, but the majority of the trees still carried their larger limbs and patches of bark. In places only the tree-trunk, a fire-carved totem pole, remained. Whirlwinds of flame had moved, and in places every burnable thing on the surface was consumed, and even tree-roots were burned out two and three feet beneath the surface.
Though weirdly interesting, these ashen fields of desolation were not wholly lifeless. Here, as elsewhere, feasters came to banquet, and good fortune brought favorites to the scene of panic and death. Flocks of gorged magpies were about, and unwontedly bold coyotes, both filled and foraging, were frequently met with. At one place a half-dozen beaver were portaging round a tumble of charred tree-trunks that obstructed the brook-channel. Fire had destroyed the food-supply, and the beaver were seeking home and harvest in other scenes. A grizzly bear was wading their pond and feasting on the dead trout that floated on the surface. Two black bears, despite terrible threats from the grizzly, claimed all the fish that came within reach of the sh.o.r.e.
They discreetly kept out of the pond.
Two fawns and their mother lay dead at the foot of a cliff. Either blinded or terrorized by fire or smoke, they apparently had leaped or fallen to death. As I gained the top in climbing to investigate, an eagle swooped angrily at me from a topless trunk. Her mate with scorched feathers lay on the rocks near by. On returning a few days later I found her still watching the lifeless one from the same perch in the dead tree.
In the heart of the burned tract was a thirty-or-forty-acre tract of forest that had escaped the fire. It was surrounded with wide though broken barriers of rock ledges. In this green oasis were numerous wild-folk refugees. Chipmunks, rats, woodchucks, and birds were startlingly abundant, but no big game. Apparently the home people had welcomed the refugees, or had received them indifferently. The only fight noticed was between mountain rats. However, this crowding and overrunning of territory when the exciting fire was over, probably made many terrible pages of animal history, before exodus and death brought a normal readjustment of life to the territory.
Wandering on across the burn toward the fire-line, I came to the place where a ragged-edged and beautiful glacier meadow had reposed, a poetic park among the spruces dark and tall. Commonly these meadows are sufficiently saturated to defy fire, but this one was burning, though slowly and with but little blaze or smoke. The fire was working toward the centre from the edges and eating downward from one to three feet. This kind of meadow usually carries a covering stratum of a kind of peat or turf which is composed almost entirely of matted gra.s.s or sedge roots that are almost free from earthy or mineral matter. These meadows lack warmth or soil sufficient to germinate tree seeds or to grow trees. Often they remain beautiful treeless gardens for generations, while wind and wash slowly bring sediment, or until a flood or landslip brings soil. The deep burning of the surface and the consequent deposit of ash on the new surface probably offered an abiding-place to the next adventurous tree seeds. Glacier meadows occasionally have this kind of ending.
Two prospectors were found at work in a spruce forest near which the fire started but which it did not reach for a week. These men said that, an hour or so after a thunder-shower of a few days before, one of the brown beetle-killed pines had sent up a smoke-column.
Apparently lightning had struck this tree. The following day a small fire was burning near it. This expanded into the forest fire. Commonly it is a standing dead tree that is set on fire by the lightning, but the bolt sometimes fires acc.u.mulated trash around the roots where it enters the earth.
Within this extensive burn the trees had stood from thirty to one hundred and forty feet high and from two hundred to three thousand to the acre, and they were from thirty to four hundred and fifty years old. A majority were about two centuries old. The predominating kinds were yellow pine, Douglas spruce, Engelmann spruce, and aspen.
Different alt.i.tudes, forest fires, and a variety of slope-exposures, along with the peculiar characteristics of each species, had distributed these in almost pure stands, an area of each kind to itself. There was some overlapping and mixing, but lodge-pole pine noticeably stood by itself.
Where first encountered, this fire was roaring through a thick second growth of lodge-pole pine. Scattered through this young growth were hundreds of dead and limbless trees killed by a fire of thirty years before. The preservative effect of their fiery death had kept these great pillars sound, though they had become checked and weathered.
They burned slowly, and that night while the fire-front was storming a ridge, these columns spread sparks and flames from split sides, or as gigantic candles blazed only at the top. Yellow pines and Douglas spruces killed in an intensely hot fire are so cooked and preserved that they will resist weathering or rot for decades. I have seen a few of these pitchy broken fellows standing erect in the depth of a century-old second generation of forest with the arms of the living trees about and above them.
Down a slope a fire moves more slowly and with lower temperature than upward on the same slope. A fire may rush in a minute up a slope which it would require a day to creep down. A fire is more all-consuming in going up, and even after years have pa.s.sed, the remains left on a slope will often enable one to determine whether a fire swept up or crept down. One peculiarity of flames in young growths on steep slopes is that they sometimes dart up the heights in tongues, leaving narrow ragged stretches of unburned trees! Usually these fiery tongues sweep in a straight line up the slope.
The intense heat of a pa.s.sing fire-front is withering at long distances. I have known a fire to blister aspen clumps that were seven or eight hundred feet from the nearest burned trees. The pa.s.sing flames may have been pushed much closer than this by slow heavy air-swells or by the brief blasts of wild wind rushes.
The habits of forest fires are largely determined by slope-inclination, wind-speed, and the quant.i.ty and quality of the fuel. In places the fire slips quietly along with low whispering, then suddenly it goes leaping, whirling, and roaring. A fire may travel less than one mile or farther than one hundred miles in a day. The ever varying slope and forest conditions in the mountains are constantly changing the speed and the enthusiasm of a fire. Where all conditions are favorable, it sweeps level stretches at a mile-a-minute speed and rolls up slopes with the speed of sound!