Part 15

“The Buttonwood,” says Michaux, “astonishes the eye by the size of its trunk and the amplitude of its head. But the white elm has a more majestic appearance, which is owing to its great elevation, to the disposition of its principal limbs, and the extreme elegance of its summit.” He considers the Buttonwood “the largest and loftiest tree of the United States.” He mentions one growing on a small island in the Ohio River, which at five feet from the ground measured forty feet and four inches in circumference; and he found another on the right bank of the Ohio that measured, at four feet from the ground, forty-seven feet in circumference, or nearly sixteen feet in diameter, and showed no marks of decay. He states that the Buttonwood is confined “to moist, wet grounds, where the soil is loose, deep, and fertile, and it is never found upon dry lands of irregular surface.”

It was probably the rapid growth and great size of the Buttonwood that caused our ancestors to plant it so extensively as a shade-tree. It rises also to a great height before it sends out any branches, thereby affording the inmates of houses the advantage of its shade, without intercepting their prospect, and without interfering with passing objects when planted by roadsides. But these noble trees, so conspicuous and so thrifty thirty years ago, have been slowly perishing from some mysterious cause which no theory can satisfactorily explain. It is generally supposed to be connected with a want of hardihood in the constitution of the tree, that renders it unable to endure all the vicissitudes of a Northern climate.

In England the same misfortune has fallen upon both the American and Oriental Plane. The late spring frosts are mentioned as the probable cause of the phenomenon, though there is but little resemblance between our climate and that of England. This tendency of the two species has prevented the general planting of them for shade and ornament. English writers give their preference to the American Plane, which they assert equals the other in size, and surpasses it in beauty of foliage. In England the American Plane has frequently attained a very great magnitude. Selby mentions one which, at forty years from the time it was planted, measured a hundred feet in height. The specific differences between the two Planetrees consist chiefly in the size and shape of their leaves, those of the Oriental Plane being smaller, and more deeply lobed or divided into segments. Both species have the same habit of annually shedding their bark, leaving the trunk with a smooth and whitish surface.

THE MYRTLE.

Among the Greeks and Romans, the oak was dedicated to Jupiter, the olive to Minerva, and the Myrtle, from the delicacy and beauty of its foliage, to Venus; and the temple of this goddess was surrounded by Myrtle groves. Hence the Myrtle and the rose have always been twined with garlands and prizes for beauty,—the one being admired for its flowers, the other for its delicate and aromatic leaves. A great deal of the romance of botany is lost to us, the inhabitants of the New World, on account of the absence from our woods of many of the plants most celebrated in classic poetry and medieval romance. We have not the heath, nor the olive, nor the ivy; and many of the humble flowers of the meadow, familiar to the reader of classical lore, are absent from our soil. Their absence, notwithstanding the beauty and elegance of many flowers and shrubs that seem to stand in the place of them, can never cease to be felt. The sacredness which a plant acquires by its association with ancient poetry and romance and with Holy Writ cannot be transferred to one of our indigenous plants of equal beauty. But there is romance in our own lives, and there are plants never mentioned in the literature of the romantic ages which are associated with certain hallowed periods and events in our youth that render them ever sacred to memory.

There are two or three plants in our own land that bear the classical name of Myrtle, not from any botanical resemblance or affinity to this plant, either in leaf or in flower, but from the aromatic odor of the leaves, like that of the true Myrtle. These plants are the Sweet-Gale, the bayberry, and the sweet-fern.

THE DUTCH MYRTLE, OR SWEET-GALE.

Along the low banks of rivers, and on the wooded shores of ponds and lakes that do not rise above the water-level, grows a slender and rather elegant bush, with dark and dull green foliage, possessing a very agreeable odor, which is perceived when the leaf is crushed. The Sweet-Gale is indigenous both in Europe and America. It is found only in wet places, where it forms knolls and copses, excluding all other plants by the density and vigor of its growth. This exclusive habit is owing to the multitude and tenacity of its roots, that form a subterranean network almost impenetrable. The Sweet-Gale is about half aquatic; it grows out of the water like the button-bush, and is, I believe, never found except in lands which are annually inundated.

It is this shrub that regales the sight with fresh verdure, rising out of the bosom of shallow waters in compact masses and forming little islets of shrubbery, without the mixture of any other plant. Through these wooded islets, on angling excursions, we propel our boat, while the surface of the lake is spangled with water-lilies, which, intermingled with the long blue spikes of pickerelweed and other aquatic flowers, while the notes of the veery and the red mavis are heard from the shore, afford the scene a kind of tropical splendor.

THE BAYBERRY.

This species has an odor very similar to that of the sweet-gale, and from its fragrance and its waxy fruit it has obtained the name of the Candleberry Myrtle. It delights in dry pastures upon the hills and uplands, to which it is a humble, but not insignificant ornament. This plant can make no very evident pretensions to beauty, having rough and crooked branches, and imperfect flowers and fruit, without any elegance of form. But its foliage is so regular, so dense, and of so bright a verdure, that it never fails to attract attention. Indeed, it displays some of the finest masses of pure green leafage to be seen among our upland shrubbery. But seldom does any tint except the green of summer appear in the Bayberry. It takes no part in the grand pageant of autumn. The fruit of this plant is a subject of great curiosity. It consists of little greenish-gray berries, stemless, and completely covering the branches like warts, thickly coated with a waxy substance, which is soluble in boiling water. This substance, when collected, makes a very hard wax of a greenish color.

THE SWEET-FERN.

Another of those humble shrubs which, though wanting in the beauty afforded by flowers, is very generally sought and admired, is the Sweet-Fern, at the very name of which we are inspired with pleasant remembrances of spring. The Sweet-Fern is a common plant on all our hills, the close companion of the bayberry, the wild rose, and the small kalmia. It is bound into all the nosegays gathered in May, and is a part of the garlands with which young girls crown the head of their May-queen, before the eglantine has put forth its leaves, and when the only flowers of the meadow are a few violets and anemones. This little shrub occupies a wide extent of territory, mingling its incense with almost every breeze that is scented by the rose. It is abundant in all the North-eastern States and the British Provinces.

The Sweet-Fern is a peculiar shrub, branching in such a manner as to form a perfect miniature tree, beautifully ramified with a neatly rounded head. The leaves are agreeably aromatic, and shaped unlike those of any other phenogamous plant, resembling a true fern-leaf, having alternate indentations that extend not quite to the midrib. It is a very grateful, not to say beautiful, ornament of our dry hills and pastures, and is more admired than any other equally homely shrub in our woods.

RELATION OF TREES TO THE SOIL.

I have spoken of trees as the purifiers and renovators of the atmosphere, as regulators of its humidity, equalizers of the electric fluid, and as safeguards against both drought and inundations; but I have not yet alluded to the fact that they are, in dense assemblages, the actual creators, in many places, of the soil upon which they stand. The trees by means of their foliage are direct fertilizers of the ground they cover, causing it to increase in bulk as long as they stand upon it. But the leaves of trees are not the only source of this increase of bulk and fertility. The lichens and mosses, and various incrustations upon their bark, and the offal of birds, insects, and quadrupeds, all contribute to the same end. Hence the most barren situations will produce good crops for several years after the removal of their wood; and from these facts we may learn why a forest is still vigorous, though it has remained for centuries upon the same ground. If it were fertilized only by the decayed foliage of the trees, it would gradually lose its fitness to promote the health and growth of the timber. But the foreign matters I have enumerated, the decayed cryptogamous plants, and the relics and deposits of animals which have lived and died there, supply the soil with nitrogenous ingredients in which decomposed leaves are wanting.

But what are the sources of all the matters which are furnished by the trees alone? They are chiefly the atmosphere and the deeper strata of the soil. The roots of the trees, penetrating to a considerable depth, draw up from the subsoil certain nutritive salts that enter into the substance of all parts of the tree. This is restored to the surface by every tree or branch that falls and moulders upon it, and the leaves increase its bulk still more by their annual decay. According to Vaupell, “the carbonic acid given out by decaying leaves, when taken up by water, serves to dissolve the mineral constituents of the soil, and it is particularly active in disintegrating feldspar and the clay derived from its decomposition.” These facts explain why the surface soil in a forest may constantly increase in bulk, without communication with any foreign sources of supply.

If a wood be situated in a valley or on a level plain, it retains all these substances for its own benefit. But if it stand upon a declivity, a part of the débris will be washed down by floods into the fields below. Hence, by preserving a growth of wood upon all barren slopes and elevations, the farmer derives benefit from it, both as a fertilizer and as a source of irrigation to the lower part of the slopes or the base of the hill. For some days after a rain, thousands of little rills are constantly oozing from the spongy bed of the wood, that cannot immediately become dry like an open surface. Hills, when either very barren or steep, are unprofitable alike for tillage or pasture. They require more manure than other grounds, and more labor in its distribution. Hence, if divested of wood, as I have often repeated, they are almost useless; while, if densely wooded, they fertilize and irrigate the lands below, protect them from winds, and afford a certain annual amount of fuel.

When I am journeying through the country and behold the rocky hills, sometimes for miles in extent, entirely bare of trees, and affording too little sustenance to support even a crop of whortleberry-bushes, where an acre would hardly pasture a single sheep, I am informed by the older inhabitants that these barren fields were since their childhood covered with forest. This wood cannot be restored, because the soil has been washed down from the surface into the plains below, and nothing remains to support a new growth of trees. And then I think, if our predecessors, instead of wrangling about theology, had left its mysteries to be explained by their pastors, and studied some of the plain laws of meteorology, this devastation had not taken place!

If these rising grounds, like most of the hills in New England, have a granite foundation and a comparatively barren surface soil, forests are the only means which can be used by nature to render them productive or useful in any way to the prosperity of agriculture. Were they stripped of trees, they could not long maintain their original fertility; for there is nothing to prevent the soil from washing down their sides, nothing to prevent inundations from copious rains, nothing to prevent their becoming rapidly parched by drought during a great part of every summer. Hence a mountain that is covered with a dense forest, how thin and meagre soever the soil may be from which the trees derive their support, is a source of perpetual fertilization to the lands below. Millions of living creatures, which are harbored in these woods, annually perish, leaving their remains upon the ground to fertilize it and increase its bulk. During their lifetime also, besides various substances which they have manipulated, they are constantly leaving deposits of many kinds upon the surface; and if the quantity thus spread upon a single acre of woodland could be measured, we should be astonished at the amount.

By means of forests, therefore, in favorable situations, a farmer obtains something apparently out of nothing, and makes the barren rocks and hills the sources of a part of the substances with which he fertilizes his grounds.

But I have said nothing of the pasturage afforded to cattle on the borders of woods. Out of every two or three tons of leaves which are cast upon the ground, a hundredweight at least is but a solidification of the gases of the atmosphere. All this would be lost to the farmer, if the upper parts of his barren elevations and the sides of his steep declivities were despoiled of their wood and shrubbery. Without this forest, tons of compost produced by the annual decay of leaves would never have been created. All that proceeds from living creatures would also be lost, because they would either have never come into existence, or they would have lived and died in another place and benefited some other region.

THE VIBURNUM.

Over all the land, save where excessive cultivation and dressing of the grounds have stripped the earth of its native garniture, the roadsides are adorned with the different species of Viburnum. We detect them in winter by their many colored branches and their finely divided spray. May clothes them with a profusion of delicate and sweet-scented flowers; lastly, autumn dyes their foliage purple and crimson, and hangs from their branches clusters of variegated fruit; so that as native ornaments of the borders of old fields and roads they are surpassed by no other shrubs. The Viburnum constitutes a great part of the underwood of our forests, thriving and bearing fruit under the deep shade of trees, but assuming a handsome shape only outside of the wood. The flowers, in circular clusters, or cymes, resemble those of the elder, but have less fragrance.

THE AMERICAN WAYFARING-TREE.

The largest and most conspicuous of this genus, and the one that seems to me to bear the most resemblance to the English Wayfaring-tree, is the Sweet Viburnum. It is a tall and wide-spreading shrub, with numerous branches and dense and elegant foliage, making a compact and well-rounded head. The leaves are single and opposite, finely serrate, and with prominent veins. Many of our shrubs produce more showy flowers, but few surpass it in the beauty of its fruit. The berries are of the size of damsons, hanging profusely from the branches like clusters of grapes. They are dark purple when ripe, with a lustre that is not seen in the grape. Just before they ripen they are crimson, and berries of this color are often blended with the ripened fruit. Like the English Wayfaring-tree, the office of this shrub seems to be to overshadow the unfrequented byways, and afford coolness and refreshment to the traveller.

THE GUELDER ROSE.

This species is common to both continents. In Europe it is cultivated under the name of Guelder Rose. In America it is known as the Snowball-tree of our gardens, and it seems to be identical with the Maple-leaved Viburnum of our woods. In the garden variety the clusters are nearly globular, consisting entirely of barren flowers, and differing from those of the wild plant in the enlargement of the florets. In the wild tree some barren florets with enlarged petals may be seen mingled with others in the cyme, chiefly encircling the disk. The fruit of this species is of a bright scarlet, and bears a superficial resemblance to cranberries, having also a similar acid taste, but a different internal structure.