A Book of the United States. Various
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hundred feet, and lie along deeply depressed beds of rivers, are clothed with the richest forests in the world. The Ohio flows under the shade of the plane and the tulip tree, like a canal dug in a nobleman’s park; while the lianas, extending from tree to tree, form graceful arches of flowers and foliage over branches of the river. Passing to the south, the wild orange tree mixes with the odoriferous and the common laurel. The straight silvery column of the papaw fig, which rises to the height of twenty feet, and is crowned with a canopy of large indented leaves, forms one of the most striking ornaments of this enchanting scene. Above all these, towers the majestic magnolia, which shoots up from that calcareous soil to the height of more than one hundred feet. Its trunk, perfectly straight, is surmounted with a thick and expanded head, the pale green foliage of which affects a conical figure. From the centre of the flowery crown which terminates its branches, a flower of the purest white rises, having the form of a rose, and to which succeeds a crimson cone. This, in opening, exhibits rounded seed of the finest coral red, suspended by delicate threads six inches long. Thus, by its flowers, its fruit, and its gigantic size, the magnolia surpasses all its rivals of the forest.
The following excellent description of the prairie country is from the pen of Mr. James Hall. ‘That these vast plains should be totally destitute of trees, seems to be an anomaly in the economy of nature. Upon the mind of an American, especially, accustomed to see new lands clothed with timber, and to associate the idea of damp and silent forests with that of a new country, the appearance of sunny plains, and a diversified landscape, untenanted by man, and unimproved by art, is singular and striking. Perhaps if our imaginations were divested of those associations, the subject would present less difficulty; and if we could reason abstractly, it might be as easy to account for the existence of a prairie as of a forest.
‘It is natural to suppose that the first covering of the earth would be composed of such plants as arrived at maturity in the shortest time. Annual plants would ripen, and scatter their seeds many times before trees and shrubs would acquire the power of reproducing their own species. In the mean time, the propagation of the latter would be likely to be retarded by a variety of accidents—the frosts would nip their tender stems in the winter—fire would consume, or the blasts would shatter them—and the wild grazing animals would bite them off, or tread them under foot; while many of their seeds, particularly such as assume the form of nuts or fruits, would be devoured by animals. The grasses, which are propagated both by the root and by seed, are exempt from the operation of almost all these casualties. Providence has, with unerring wisdom, fitted every production of nature to sustain itself against the accidents to which it is most exposed, and has given to those plants which constitute the food of animals, a remarkable tenacity of life; so that although bitten off, and trodden, and even burned, they still retain the vital principle. That trees have a similar power of self protection, if we may so express it, is evident from their present existence in a state of nature. We only assume that in the earliest state of being, the grasses would have the advantage over plants less hardy, and of slower growth; and that when both are struggling together for the possession of the soil, the former would at first gain the ascendancy; although the latter, in consequence of their superior size and strength, would finally, if they should ever get possession of any portion of the soil, entirely overshadow and destroy their humble rivals.
‘We have no means of determining at what period the fires began to sweep over these plains, because we know not when they began to be inhabited. It is quite possible they might have been occasionally fired by lightning, previous to the introduction of that element by human agency. At all events, it is very evident that as soon as fire began to be used in this country by its inhabitants, the annual burning of the prairies must have commenced. One of the peculiarities of this climate is the dryness of its summers and autumns. A drought often commences in August, which, with the exception of a few showers towards the close of that month, continues throughout the season. The autumnal months are almost invariably clear, warm, and dry. The immense mass of vegetation with which this fertile soil loads itself during summer, is suddenly withered, and the whole surface of the earth is covered with combustible materials. This is especially true of the prairies where the grass grows to the height of from six to ten feet, and being entirely exposed to the sun and wind, dries with great rapidity. A single spark of fire, falling any where upon these plains at such a time, would instantly kindle a blaze, which would spread on every side, and continue its destructive course as long as it should find fuel. Travellers have described these fires as sweeping with a rapidity which renders it hazardous to fly before them. Such is not the case; or it is true only of a few rare instances. The flames often extend across a wide prairie, and advance in a long line. No sight can be more sublime than to behold in the night a stream of fire of several miles in breadth, advancing across these wide plains, leaving behind it a black cloud of smoke, and throwing before it a vivid glare which lights up the whole landscape with the brilliancy of noonday. A roaring and cracking sound is heard like the rushing of a hurricane. The flame, which in general rises to the height of about twenty feet, is seen sinking and darting upwards in spires, precisely as the waves dash against each other, and as the spray flies up into the air; and the whole appearance is often that of a boiling and flaming sea, violently agitated. The progress of the fire is so slow, and the heat so great, that every combustible object in its course is consumed. Wo to the farmer whose ripe cornfields extend into the prairie, and who suffers the tall grass to grow in contact with his fences! The whole labor of the year is swept away in a few hours. But such accidents are comparatively unfrequent, as the preventive is simple, and easily applied.
‘It will be readily seen, that as soon as these fires commenced, all the young timber within their range must have been destroyed. The whole state of Illinois, being one vast plain, the fires kindled in different places, would sweep over the whole surface, with a few exceptions, of which we are now to speak. In the bottom-lands, and along the margins of streams, the grass and herbage remain green until late in the autumn, owing to the moisture of the soil. Here the fire would stop for want of fuel, and the shrubs would thus escape from year to year, and the outer bark acquire sufficient hardness to protect the inner and more vital parts of the tree. The margins of the streams would thus become fringed with thickets, which, by shading the ground, would destroy the grass, while it would prevent the moisture of the soil from being rapidly evaporated, so that even the fallen leaves would never become so thoroughly dry as the grass of the prairies, and the fire here would find comparatively little fuel. These thickets grow up into strips of forests, which continue to extend until they reach the high table-land of the prairie; and so true is this, in fact, that we see the timber now, not only covering all the bottom-lands and hill sides, skirting the streams, but wherever a ravine or hollow extends from the low grounds up into the plain, these are filled with young timber of more recent growth. But the moment we leave the level plane of the country, we see the evidences of a continual struggle between the forest and the prairie. At one place, where the fire has on some occasion burned with greater fierceness than usual, it has successfully assailed the edges of the forest, and made deep inroads; at another, the forest has pushed out long points or capes into the prairie.
‘It has been suggested that the prairies were caused by hurricanes, which had blown down the timber and left it in a condition to be consumed by fire, after it was dried by laying on the ground. A single glance at the immense region in which the prairie surface predominates, must refute this idea. Hurricanes are quite limited in their sphere of action. Although they sometimes extend for miles in length, their track is always narrow, and often but a few hundred yards in breadth. It is a well known fact, that wherever the timber has been thus prostrated, a dense and tangled thicket shoots up immediately, and, protected by the fallen trees, grows with uncommon vigor.
‘Some have imagined that our prairies have been lakes; but this hypothesis is not tenable. If the whole state of Illinois is imagined to have been one lake, it ought to be shown that it has a general concavity of surface. But so far from this being true, the contrary is the fact; the highest parts of the state are in its centre. If we suppose, as some assert, that each prairie was once a lake, we are met by the same objection; as a general rule, the prairies are highest in the middle, and have a gradual declivity towards the sides; and when we reach the timber, instead of finding banks corresponding with the shores of a lake, we almost invariably find valleys, ravines, and water-courses depressed considerably below the general level of the plain.
‘Wherever