The most graceful of our native trees is the White or Silver Birch. It is the very antipodes among trees of the solid unbending oak. The slim stem, scarcely ever a foot in diameter, tapers away almost to nothing at a height of fifty or sixty feet. This is at full maturity at forty or fifty years; thereafter it makes little progress, and it is believed not to reach far beyond its hundredth year. It has the singular reputation for producing a bark that is more enduring than its timber. In spite of its effeminate grace it is a most hardy tree, and stands alone on the bleakest hillsides, and is the only tree that endures the Birch. The leaf varies slightly in outline from oval with a point to a rhombic form, with a long slender stalk, and the edges are doubly toothed. The silvery-white bark is continually discarding its outermost layer, which peels off in ragged, tissue-paper-like strips, revealing the newer, whiter bark beneath. In this country it is used in tanning, but in the far Northern parts of Europe it is put to a variety of uses. The inflorescence is a catkin, the sexes separate, but borne by the same tree. The flowers of the pendulous male catkin consist each of a single sepal with two stamens, the filaments of which are forked, each branch bearing one anther cell, so that each stamen looks like two. The female spike, which is more erect, and shorter, is composed of three-lobed bracts, each containing two or three flowers. These are simply two-celled ovaries, with two styles and stigmas. The fruit is round, flattened, with a notched broad wing. It flowers in April and May.
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