3. INDIAN SUMMER ENCAMPMENT, ALASKA.
The latter, comprising the islands within the Arctic Circle, form a belt, more or less broad, bounded by the continental shores of the North Polar seas, and gradually merging toward the south into the forest-region, which encircles them with a garland of evergreen coniferæ. This treeless zone bears the name of the “barren grounds,” or the “barrens,” in North America, and of “tundri” in Siberia and European Russia. Its want of trees is caused not so much by its high northern latitude as by the cold sea-winds which sweep unchecked over the islands or the flat coast-lands of the Polar Ocean, and for miles and miles compel even the hardiest plant to crouch before the blast and creep along the ground.
Nothing can be more melancholy than the aspect of the boundless morasses or arid wastes of the tundri. Dingy mosses and gray lichens form the chief vegetation, and a few scanty grasses or dwarfish flowers that may have found a refuge in some more sheltered spot are unable to relieve the dull monotony of the scene.
In winter, when animal life has mostly retreated to the south or sought a refuge in burrows or in caves, an awful silence, interrupted only by the hooting of a snow-owl or the yelping of a fox, reigns over their vast expanse; but in spring, when the brown earth reappears from under the melted snow and the swamps begin to thaw, enormous flights of wild birds appear upon the scene and enliven it for a few months. An admirable instinct leads their winged legions from distant climes to the Arctic wildernesses, where in the morasses or lakes, on the banks of the rivers, on the flat strands, or along the fish-teeming coasts, they find an abundance of food, and where at the same time they can with greater security build their nests and rear their young. Some remain on the skirts of the forest-region; others, flying farther northward, lay their eggs upon the naked tundra. Eagles and hawks follow the traces of the natatorial and strand birds; troops of ptarmigans roam among the stunted bushes; and when the sun shines, the finch or the snow-bunting warbles his merry note.
While thus the warmth of summer attracts hosts of migratory birds to the Arctic wildernesses, shoals of salmon and sturgeons enter the rivers in obedience to the instinct that forces them to quit the seas and to swim stream upward, for the purpose of depositing their spawn in the tranquil sweet waters of the stream or lake. About this time also the reindeer leaves the forests to feed on the herbs and lichens of the tundra, and to seek along the shores fanned by the cooled sea-breeze some protection against the attacks of the stinging flies that rise in myriads from the swamps. Thus during several months the tundra presents an animated scene, in which man also plays his part. The birds of the air, the fishes of the water, the beasts of the earth, are all obliged to pay their tribute to his various wants, to appease his hunger, to clothe his body, or to gratify his greed of gain.
But as soon as the first frosts of September announce the approach of winter, all animals, with but few exceptions, hasten to leave a region where the sources of life must soon fail. The geese, ducks, and swans return in dense flocks to the south; the strand-birds seek in some lower latitude a softer soil which allows their sharp beak to seize a burrowing prey; the water-fowl forsake the bays and channels that will soon be blocked up with ice; the reindeer once more return to the forest, and in a short time nothing is left that can induce man to prolong his stay in the treeless plain. Soon a thick mantle of snow covers the hardened earth, the frozen lake, the ice-bound river, and conceals them all—seven, eight, nine months long—under its monotonous pall, except where the furious north-east wind sweeps it away and lays bare the naked rock.
This snow, which after it has once fallen persists until the long summer’s day has effectually thawed it, protects in an admirable manner the vegetation of the higher latitudes against the cold of the long winter season. For snow is so bad a conductor of heat, that in mid-winter in the high latitude of 78° 50° (Rensselaer Bay), while the surface temperature was as low as -30°, Kane found at two feet deep a temperature of -8°, at four feet +2°, and at eight feet +26°, or no more than six degrees below the freezing-point of water. Thus covered by a warm crystal snow-mantle, the northern plants pass the long winter in a comparatively mild temperature, high enough to maintain their life, while, without, icy blasts—capable of converting mercury into a solid body—howl over the naked wilderness; and as the first snow-falls are more cellular and less condensed than the nearly impalpable powder of winter, Kane justly observes that no “eider-down in the cradle of an infant is tucked in more kindly than the sleeping-dress of winter about the feeble plant-life of the Arctic zone.” Thanks to this protection, and to the influence of a sun which for months circles above the horizon, and in favorable localities calls forth the powers of vegetation in an incredibly short time, even Washington, Grinnell Land, and Spitzbergen are able to boast of flowers. Morton plucked a crucifer at Cape Constitution (80° 45’ N. lat.), and, on the banks of Mary Minturn River (78° 52’), Kane came across a flower-growth which, though drearily Arctic in its type, was rich in variety and coloring. Amid festuca and other tufted grasses twinkled the purple lychnis and the white star of the chickweed; and, not without its pleasing associations, he recognized a solitary hesperis—the Arctic representative of the wall-flowers of home.
4. ROCKS AND ICE.
Next to the lichens and mosses, which form the chief vegetation of the treeless zone, the cruciferæ, the grasses, the saxifragas, the caryophyllæ, and the compositæ are the families of plants most largely represented, in the barren grounds or tundri. Though vegetation becomes more and more uniform on advancing to the north, yet the number of individual plants does not decrease. When the soil is moderately dry, the surface is covered by a dense carpet of lichens (Corniculariæ), mixed in damper spots with Icelandic moss. In more tenacious soils, other plants flourish, not however to the exclusion of lichens, except in tracts of meadow ground, which occur in sheltered situations, or in the alluvial inundated flats where tall reed-grasses or dwarf willows frequently grow as closely as they can stand.