But, though only one tree may grow, this in due time shades the grass, a circle of young trees rise around it, and these in turn carry forward the work of winning territory. At last the park is overgrown with trees!
Glacier meadows may be seen in all stages of evolution. The lake-basin gouged by a glacier goes through many changes before it is covered by a forest and forgotten. No sooner does ice vanish and a glacier lake appear than its filling-in is commenced. Landslips and snow-slides thrust boulders and cliff-fragments into it; running water is constantly depositing sand and sediment upon its bottom. Sedge and moss commence covering its surface as soon as its water becomes shallow. In due time it becomes a bog with a thick covering like a wet mattress, composed of the matted roots of sedge and grass. Over this, wind and water deposit earthy matter, but centuries may pass before the bog is filled in sufficiently to have a dry surface and produce grass and flowers and finally trees.
Once while strolling through a forested flat in central Colorado, I concluded from the topography of the country that it must formerly have been a glacier lake. I procured tools and sank a shaft into the earth between the spruces. At a depth of two feet was a gravelly soil-deposit, and beneath this a matting of willow roots and sedge roots and stalks. These rested in a kind of turf at water-level, beneath which were boulders, while under these was bed-rock. Numerous romantic changes time had made here.
Many of these meadows are as level as the surface of a lake. Commonly the surface is comparatively smooth, even though one edge may be higher than the other. I measured one meadow that was three thousand feet long by two hundred and fifty feet wide. Tree-ranks of the surrounding forest crowded to its very edge. On the north the country extended away only a foot or two higher than meadow-level. On the south a mountain rose steeply, and this surface of the meadow was four feet higher than the one opposite. The up-the-mountain end was about three feet higher than the end which had been the old outlet of the lake. The steep south shore had sent down more material than the level one on the north. In fact, water-level on the north shore, though concealed by grass, was almost precisely the same as when the waters of the lake shone from shore to shore. In one corner of the meadow was an aspen grove. From the mountain-side above, a landslide had come down. Rains had eroded this area to bed-rock and had torn out a gully that was several feet wide on the slope below. This washed material was spread out in a delta-like deposit on the surface of the meadow. Aspens took possession of this delta.
Glacier meadows are usually longer-lived than other mountain parks. In favorable places they sometimes endure for centuries. Commonly they are slowly replaced by the extending forest. The peaty, turfy growth which covers them is of fine matted roots, almost free of earthy or mineral matter, and often is a saturated mattress several feet in thickness. The water-level is usually at the surface, but during an extremely dry time it may sink several inches or even a few feet. If fires run during a dry period of this kind, the fire will burn to water-level. The ashes of this fire, together with the mineral matter which it concentrates, commonly form a soil-bed which promptly produces trees. Sometimes, however, grass returns. Thus, while fire brings forth many meadows in the forest, it sometimes is the end of one evolved from glacial action. A landslip often plunges a peninsula of soil out upon a glacial meadow. This is usually captured by trees in a year or two.
These parks make ideal camping-places,—wild, beautiful, and alluring in every season. I have enjoyed them when they were white with snow, mysterious with cloud and mist, romantic with moonlight, and knee-deep in the floral wealth of June. Often I have burst out upon a sunny meadow hidden away in the solitude of the forest. As it lies silent in the sunshine, butterflies with beautifully colored wings circle lightly above its brilliant masses of flowers. Here bears prowl, deer feed, and birds assemble in such numbers that the park appears to be their social centre. In these wild gardens the matchless solitaire is found. Often he sings from the top of a spruce and accompanies his song by darting off or upward on happy wings, returning and darting again, singing all the time as if enchanted.
Among the hundreds of these happy resting-grounds in which I have camped, one in the San Juan Mountains has left me the most memories. I came there one evening during a severe gale. The wind roared and thundered as impressively as breakers on a rock-bound shore. By midnight the storm ceased, and the tall trees stood as quietly as if content to rest after their vigorous exercise in the friendly wrestling-match with the wind. The spruces had become towering folded flags of fluffy black. After the gale the sky was luminous with crowding stars. I lingered in the centre of the opening to watch them. The heavens appeared to be made of many star-filled skies, one behind the other. The farthest one was very remote, while the closest seemed strangely near me, just above the tops of the trees.
CAPITOL PEAK AND SNOW MASS MOUNTAIN FROM GALENA PARK
Many times I have come out of the subdued light of the pathless forest to enjoy these sunny openings. Often I have stood within them watching the butterflies circling in the sun or a deer and her fawns feeding quietly across, and, as I looked, I have listened to the scolding of the squirrel and the mellow ringing of the woodpecker far away in the forest. Here I have watched the coming storm, have enjoyed its presence, and in its breaking have seen the brilliant bow rest its foundations in front of the trees just across the meadow. Sometimes the moon showed its soft bow in the edge of the advancing or the breaking storm.