- White birch trees generally grow to be 40 to 50 feet tall and 15 to 30 feet wide, but in the wild, trees may grow as tall as 100 feet. Trees are pyramidal when young; however, over time, they become more oval in form. A mature white birch has graceful, drooping branches. The main trunk remains upright. Tree crowns are open and irregular. The growth rate in most locations is considered moderate to fast.
- White birch trees have smooth, slightly peeling bark. Although the bark can easily be removed, it will not exfoliate on its own. Betula pedula develops its characteristic white bark with black vertical fissures while trees are young. It will turn progressively darker with age. Betula papyrifera, on the other hand, is reddish-brown while young. It becomes increasingly lighter with age. The branches and twigs of both species are slender, warty and drooping in form. Twigs possess small resin glands. The production of resin is thought to deter grazing herbivores.
- White birch leaves are simple and vaguely triangular, possessing a wide base and long, pointed tips. Margins of leaves are finely toothed along the edges. Leaves are alternately arranged, which means they will appear at unequal places on sides of twigs. Leaves are glossy green on top and slightly less vibrant on the bottom. They are 1 to 3 inches long. In the fall, leaves will turn yellow just before they fall from trees. Infestations of birch leaf miner, which is common, cause leaves to turn brown.
- White birch trees bloom in the spring. Trees will produce male and female catkins, commonly in pairs of two. Male catkins may grow as long as 3½ inches while female catkins remain approximately 1 inch in length. White birch fruit consists of small but elongated cones, which are about three times as long as they are wide. Cones start out green, turning brown when ripe in the fall. Ripe cones are easily broken into inconspicuous nutlets, which are held in cylindrical catkins with two wings and three-lobed bracts.
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