A year among the trees

by Wilson Flagg

All species of insects multiply in cultivated grounds, while the birds, with a few exceptions, that feed upon them, can find a nursery and protection only in the woods. “The locust,” says George P. Marsh, “which ravages the East with its voracious armies, is bred in vast open plains, which admit the full heat of the sun to hasten the hatching of the eggs, gather no moisture to destroy them, and harbor no bird to feed upon their larvæ. It is only since the felling of the forests of Asia Minor and Cyrene that the locust has become so fearfully destructive in those countries; and the grasshopper, which now threatens to be almost as great a pest to the agriculture of North American soils, breeds in seriously injurious numbers only where a wide extent of surface is bare of woods.”

Some men destroy trees and shrubbery in their borders, because they are supposed to harbor insects. But if this be true, it is because they are not sufficient in extent to shelter the birds that feed upon them. The insects that multiply upon our lands deposit their eggs some in the soil, some on the branches of trees and upon fences and buildings. They are nowise dependent on a wild growth of wood and shrubbery. These pests of agriculture need nothing better than the under edge of a clapboard or a shingle whereon to suspend their cocoons or lay their eggs. So minute are the objects that will afford them all the conveniences they need, when hatching and when passing through all their transformations, till they become perfect insects, that no artifice or industry of man can deprive them of their nurseries, or appreciably lessen their numbers. All inventions and appliances used to rid the trees and grounds of these pests never destroyed more than one in a million of their whole number. It is not in the power of man, with all his science, unassisted by birds, to prevent the multiplication of insects from being the cause of his own annihilation. But the farmer, when he destroys the border shrubbery in his fields and the coppice and wood on his hills, exterminates the birds by hosts, while the mischievous boy with his gun destroys only a few individuals. The clipped hedge-row, which is often substituted for a border of wild shrubbery, may assist in breeding insects; but the birds never build their nests in a hedge-row, unless it be a long-neglected one.

I have in another essay spoken of the scarcity of birds and other animals in the primitive forest. They are not numerous there, because the forest would yield them only a scanty subsistence. The forest border is their nursery and their shelter, but their best feeding-places are the cultivated grounds. There is not a single species whose means of subsistence are not increased by the clearing of the forest and the cultivation of the land; but they require a certain proportion of wild wood for their habitation. Very few species build their nests in the trees and shrubbery of our gardens, unless they are near a wood. In that case the catbird often nestles in the garden, that during the rearing of its young it may be near the grounds that produce larvæ. Most of the woodpeckers, the sylvias, and the small thrushes, including some of our most valuable birds, cannot rear their young except in a wild wood. Yet all these, solitary as they are in their habits, increase under favorable circumstances with the multiplication of insects consequent upon the culture of the soil. It may be affirmed as an indisputable truth, that if their increase were not checked by the sporting habits of men and boys, and the clearing and grubbing habits of “model farmers,” birds of every species would increase in the same ratio with the multiplication of their insect food, and proportionally diminish their ravages.

THE BLACK OR CHERRY BIRCH.

The epithets “black,” “white,” “red,” and “yellow,” which are so commonly misapplied to certain trees for specific distinction,—a misapplication very remarkable with reference to the poplar,—are very well applied to the different species of birch, and serve as intelligible marks of identity. The Black Birch, for example, is clothed with a dark-colored bark, which comes nearer a pure black than any other color. No person would dispute the color of the white birches; that of the yellow birch, though not pure, would never be mistaken for anything but yellow; and the bark of the red birch, though nearly white, is so thoroughly stained with red as to demonstrate the propriety of its name.

The Black Birch is also named the Cherry Birch, from the resemblance of the tree to the American black cherry. Its inner bark has the flavor of checkerberry, and its wood some of the colors of mahogany; and it has received names corresponding with these characters, such as Sweet Birch and Mahogany Birch, and was formerly a favorite material for cabinet furniture. The bark of this species and of the yellow birch has very little of that leathery or papyraceous quality which is so remarkable in that of the white birches. This species does not extend so far north as the others, but has a wider geographical range in and below the latitude of New England.

The Black Birch puts forth its flowers very early in the year, of a deep yellow and purple and sensibly fragrant. The foliage also appears early. The leaves are finely serrate, oval, with conspicuous veins, turning yellow in the autumn. Not one of the birches ever shows a tint approaching to red or purple in its foliage. The Black Birch delights in moist grounds, and commonly occupies a stand on mountain slopes and on the banks of rivers. When growing singly on a plain, or in an open space, it takes a hemispherical shape, with its terminal and lower branches drooping to some extent like those of the elm. This tree is conspicuous on craggy precipices, among the mountains, where it extends its roots into the crevices of the rocks, and spreads its branches over chasms and hollows. On these sites it displays a variety of picturesque forms, corresponding with the rudeness and the wildness of the scenery around it. Nature has furnished this tree with a chaffy or winged seed, which is soon wafted and sown by the winds upon mountain-sides and among inaccessible rocks, where the soil collected in thin fissures supplies it with sustenance.

THE YELLOW BIRCH.

The Yellow Birch, named excelsa by botanists, from its superior height, is perhaps the most beautiful of the genus. Its branches are extremely numerous, long and slender, corresponding with the superior length of its trunk, and they are prone, like those of the elm, to equality in size, and to divergency from nearly a common centre. Indeed, where this tree has grown as an isolated standard, it commonly displays a very symmetrical head, differing in form from a perfect elm only by less inclination to droop. The leaves of this species have much of the same quality which I have remarked as peculiar to the beech, every leaf standing erect upon its stem. The flexible appearance of the tree is derived entirely from its slender flowing branches.

The Yellow Birch is very abundant in Maine and New Brunswick, and formerly constituted the greater part of the wood which was brought into Massachusetts for fuel. Many of the logs were of immense size before the primitive forest was removed. At the present day we seldom find one more than eighteen inches in diameter, though many slender individuals still occupy our woods. It delights in cold, damp soils, and I have seen the finest standards near springs on an open hillside. The Yellow Birch derives its name from the golden hue of the bark that covers the trunk and larger limbs. This silken bark, which is rolled into multitudes of soft ringlets, is peculiar to this tree.