The indigenous trees of America, or rather of the Atlantic side of this continent, are remarkable not only for their superior autumnal hues, but also for the shorter period during which the foliage remains on the trees and retains its verdure. Our fruit-trees, which are all exotics, retain their foliage long after our forest-trees are leafless; and if we visit an arboretum in the latter part of October, we may select the American from the foreign species, by observing that the latter are still green, while the others are either entirely denuded, or in that colored array which immediately precedes the fall of the leaf. The exotics may likewise be distinguished in the spring by their precocity,their leaves being out a week or ten days earlier than the leaves of our trees. Hence, if we take both the spring and autumn into the account, the foreign, or rather the European species, show a period of verdure of three or four weeks' greater duration than the American species. Many of the former, like the Weeping Willow, do not lose their verdure, nor shed their leaves, until the first wintry blasts of November freeze them upon their branches and roll them into a crisp.
In a natural forest there is a very small proportion of perfectly formed trees; and these occur only in such places as permit some individuals to stand isolated from the rest, and to spread out their branches to their full extent. When we walk in a forest, we observe several conditions which are favorable to this full expansion of their forms. On the borders of a pond or morass, or of an extensive quarry, the trees extend their branches into the opening, but, as they are cramped on the opposite side, they are only half developed. But this expansion takes place on the side that is exposed to view: hence the incomparable beauty of a wood on the borders of a pond, or on the banks of a river, as viewed from the water; also of a wood on the outside of an islet in a lake or river.
Fissures or cavities sometimes occur in a large rock, allowing a solitary tree that has become rooted there to attain its full proportions. It is in such places, and on sudden eminences that rise above the forest-level, on a precipice, for example, that overlooks the surrounding wood, that the forest shows individual trees possessing the characters of standards, like those we see by the roadsides and in the open field. We must conclude, therefore, that a primitive forest must contain but a very small proportion of perfect trees: these are, for the most part, the occupants of land cleared by cultivation, and may be found also among the sparse growth of timber that has come up in pasture land, where the constant browsing of cattle prevents the formation of any dense assemblages.
In the opinion of Whately, grandeur is the prevailing character of a forest, and beauty that of a grove. This distinction may seem to be correct, when such collections of wood exhibit all their proper characters: but perfectly unique forms of wood are seldom found in this country, where almost all the timber is of spontaneous growth. We have genuine forests; but other forms of wood are of a mixed character, and we have rather fragments of forest than legitimate groves. In the South of Europe many of the woods are mere plantations, in which the trees were first set in rows, with straight avenues, or vistas, passing directly through them from different points. In an assemblage of this kind there can be nothing of that interesting variety observed in a natural forest, and which is manifestly wanting even in woods planted with direct reference to the attainment of these natural appearances. "It is curious to see," as Gilpin remarks, "with what richness of invention, if I may so speak, Nature mixes and intermixes her trees, and shapes them into such a wonderful variety of groups and beautiful forms. Art may admire and attempt to plant and to form combinations like hers; but whoever observes the wild combinations of a forest and compares them with the attempts of Art has little taste, if he do not acknowledge with astonishment the superiority of Nature's workmanship."
When a tract is covered with a dense growth of tall trees, especially of Pines, which have but little underbrush, the wood represents overhead a vast canopy of verdure supported by innumerable lofty pillars. No one could enter these dark solitudes without feeling a deep impression of sublimity, especially if it be an hour of general stillness of the winds. The voices of animals and of birds, particularly the hammering of the woodpecker, serve to magnify our perceptions of grandeur. A very slight sound, during a calm in one of these deep woods, like the ticking of a clock in a vast hall, has a distinctness almost startling, especially if there be but little undergrowth. These feeble sounds afford one a more vivid sense of the magnitude of the place than louder sounds, that differ less from those we hear in the open plain. The canopy of foliage overhead and the absence of undergrowth are favorable to those reverberations which are so perceptible in a Pine wood.
In a grove we experience different sensations. Here pleasantness and cheerfulness are combined, and the feeling of grandeur is excited only perhaps by the sight of some noble tree. In a grove the trees are generally well formed, many of them being nearly perfect in their proportions. Their shadows are cast separately upon the ground, which is green beneath them as in an orchard. If we look upon them from a near eminence, we observe a variety of outlines, and may identify the different species by their shape, while in the forest we see one unbroken mass of foliage. A wild-wood is frequently converted into a grove by clearing it of undergrowth and leaving the space a grassy lawn. It may then yield us shade, coolness, and other agreeable sensations of a cultivated wood, but the individual trees always retain their gaunt and imperfect shapes.
The greater part of the woodland of this country partakes of the characters of both forest and grove, exhibiting a pleasant admixture of each, combined with pasture and thicket. In Great Britain the woods are chiefly groves and parks: a wild-wood of spontaneous growth is now rare in that country, once renowned for the extent and beauty of its forests. Most of our American woods are fragments of forest, particularly in the Western States, where they stand out prominently, and deform the landscape by presenting a perpendicular front of naked pillars, unrelieved by any foliage. They remind one of those houses, in the city, which have been cut asunder to widen a street, leaving the interior rooms and partition-walls exposed to view. These sections of wood are the grand picturesque deformity of a country lately cleared. In the older settlements, a recent growth of wood has in many instances come up outside of these palisades, serving in a measure to conceal their baldness.
The most lovely appearances in landscape are caused by the spontaneous growth of miscellaneous trees, some in dense assemblages and some in scattered groups, with here and there a few single trees standing in open space. Such is the scenery of considerable portions of the Atlantic States, both North and South. These varied assemblages of wood and shrubbery are the characteristic features of the landscape in the older villages of New England, and indeed of all the States that were established before the Revolution. But the New-England system of farmingso much abhorred by those who wish to bring agriculture to such a state of improvement as shall make it profitable exclusively to capitalistshas been more favorable to the sylvan beauty of the landscape than that of any other part of the continent. At the South, especially, where agriculture is carried on in large plantations, we see wide fields of tillage, and forest groups of corresponding size. But the small and independent farming of New Englandas favorable to general happiness as it is to beautiful sceneryhas produced a charming variety of wood, pasture, and tillage, so agreeably intermixed that one is never weary of looking upon it. The varied surface of the landscape, in the uneven parts which are not mountainous, has increased these advantages, producing an endless multitude of those limited views which may be termed picturesque.