Wayside and Woodland Trees: A pocket guide to the British sylva

by Edward Step

"The Lady of the Woods," as Coleridge christened the Birch, is at once the most graceful, the hardiest, and the most ubiquitous of our forest trees. It grows throughout the length and breadth of our islands, and seems happy alike on a London common, in a suburban garden, or far up in the Scottish highlands (2500 feet). It penetrates farther north than any other tree, and its presence is a great boon to the natives of Lapland. It will grow where it is subjected to great heat, as well as where it must endure extreme cold, with its slender roots exploring the beds of peat, the rich humus of the old wood, or the raw soil of the mountain-side, where it has to cling to rocks and a few mosses. Given plenty of light, and it seems to care for little else. Though a mere shrub in the far north, with us the Birch has a trunk sometimes as tall as eighty, but more frequently fifty feet, and a girth of from two to three feet. In its first decade it increases in height at the rate of a foot and a half or two feet in a year; but, of course, there is little breadth to be built up at the same time. It reaches maturity in half a century, and before the other half is reached the Birch will have passed away.

The bark of the Birch is more enduring than its timber, which may be partly due to its habit of casting off the outer layer in shreds, like fine tissue-paper, from time to time. The greater part of the bark is silvery white, which adds to the apparent slenderness of the tree, and makes it conspicuous from a long distance; for the attenuated and drooping branches, dressed in small and loosely hung leaves, sway so constantly

that the trunk is scarcely hidden. The glossy, leathery leaves vary in shape from a triangular form to a pointed oval, their edges doubly toothed, and their footstalks long and slender.

About April the hanging catkins of the Birch, which were in evidence in the previous autumn, have matured and become dark crimson; the scales separate and expose the two stamens of each flower, which has a single sepal. The female flowers are in a short, more erect spike, which consists of overlapping scales (bracts), each containing two or three flowers. The flowers have neither petals nor sepals, each consisting merely of an ovary with two slender styles. After fertilization the female spike has developed into a little oblong cone. The minute nuts have a pair of delicate wings to each, and as they are set free from the cones they flutter on the breeze like a swarm of small flies. The moss that usually covers the ground beneath the Birch will be found in October to be thickly speckled with these fruits, which are something more than seeds, as they are commonly termed; they are really analogous to the acorn—a nut within a thin shell. The tree sometimes begins to produce seed when only fifteen years old; but, as a rule, it is ten years older before it bears, and thereafter it has a crop every year.

It is strange how so striking and graceful a tree could have been so persistently ignored by the old school of landscape painters, when one remembers with what good effect modern artists have utilized it. In this connection we need not apologize for quoting at length a description of the tree from the artist's point of view, because it also gives attention to those points one would like the rambler to notice. Mr. P. G. Hamerton in his Sylvan Year, says—

"The stem ... of the Silver Birch is one of the masterpieces of Nature. Everything has been done to heighten its unrivalled brilliance. The horizontal peeling of the bark, making dark rings at irregular distances, the brown spots, the dark colour of

the small twigs, the rough texture near the ground, and the exquisite silky smoothness of the tight white bands above, offer exactly that variety of contrast which makes us feel a rare quality like that smooth whiteness as strongly as we are capable of feeling it. And amongst the common effects in all northern countries, one of the most brilliant is the opposition of birch trunks in sunshine against the deep blue or purple of a mountain distance in shadow. At all seasons of the year the beauty of the birch is attractive and peculiarly its own. The young beech may remind you of it occasionally under strong effects of light, and is also very graceful, but we have no tree that rivals the

birch in its own qualities of colour and form, still less in that air and bearing which are so much more difficult to describe. In winter you see the full delicacy of the sprays that the lightest foliage hides, and in early spring this tree clothes itself, next after the willow, with tiny triangular leaves, inexpressibly light in the mass, so that from a distance they have the effect of a green mist rather than anything more material. When the tree is isolated sufficiently to come against the sky, you may see one of the prettiest sights in Nature—the pure deep azure of heaven, with the silvery white and fresh green of the birch in opposition. And yet it is not a crude green, for there is a good deal of warm red in it, which gives one of those precious tertiaries that all true colourists value."

Linnæus named our common Birch Betula alba; but more than a century ago Ehrhart pointed out that there were two well-defined forms of the tree, which he proposed to separate as distinct species under the names of B. verrucosa and B. pubescens. Hooker regards the first of these as the typical form, for which he properly retains the Linnæan name. It is distinguished by having the base of the bole covered with coarse, rough, and blackish bark, the smooth leaves looking as though their base had been cut off, and the twigs warty. The B. pubescens of Ehrhart appears to be a variety of Fries' B. glutinosa, which Hooker treats as a sub-species of B. alba. The bark at its base is smooth and white, its downy leaves have a triangular base, and its twigs are free from warts. It sometimes assumes a bush-like form.