Birches White, Sweet, and Silver
The different birches are beautiful and useful
The various species of birch trees are distinctive, easily identified, elegant, and have been historically useful to humans for making medicines and tools.
Most people are familiar with white or paper birch, due to its bright white bark and graceful habits, which lend a gladdening light to the forest. The bark curls off in wide strips, even while the tree is alive. Indians peeled bark in large sheets from recently downed trees, creasing, folding, and securing the bark with string (such as basswood rootlets) through holes punched in the edges, to make waterproof containers for carrying and cooking. When folded with the pinkish-orange inner layers to the outside, the containers are also fireproof and may be placed directly into a low-burning fire, as long as they are filled with water to whatever level the flames may reach. The white outer layers, when shredded to thin, narrow strips, catch fire easily, making excellent tinder. However, peeling too much bark from a live tree can kill it, especially if the peeled strip goes all the way around the trunk.
More common but less readily recognized is the sweet or black birch, which has dark gray-black, non-peeling bark with raised horizontal lines. Wild cherry bark looks similar, usually (but not always) with a reddish-brown cast. Black birch has oval, sawtoothed leaves, while wild cherry has long, narrow leaves. In winter, the two species can be distinguished by the smell of their inner bark, detected by scratching and sniffing a twig. Wild cherry smells like bitter almond, a bit harsh, while sweet birch bark bears the sweet fragrance of wintergreen. The inner bark contains methylsalicylic acid, the same substance which gives wintergreen berries and leaves their scent. Sweet birch bark tastes good and can be chewed for a refreshing pick-me-up in the woods. It can even be used to make a not-so-tasty but nutritious sort of bread in emergencies.
Methylsalicylic acid is also medicinal. Preparations made from black birch, much more common than the somewhat endangered wintergreen plant, are used as an external rub for sore muscles and arthritis, an internal remedy for bladder infections, and a cooling medicine for various conditions of excess heat. The twigs make a tasty tea. To make a tincture (an alcohol extract), the inner bark must be peeled from the twigs, a tedious task that is ideally done when the sap is moving most vigorously, either up to the buds in spring or down to the roots in fall.
Sweet birch trees may be tapped in April, when the trees are producing flowers, both the male catkins that hang elegantly from the twigs, and the conelike female structures that remain on the trees until winter, when birds scatter the tiny, three-lobed scales over the snow. In Alaska, which lacks sugar maples, birches are tapped for making syrup, although it is not nearly as sweet as maple and requires a lot more sap. (See also the blog Sweet Birch.)
Yellow or silver birch, with pale, shiny bark that peels in small strips, also contains methylsalicylic acid, but in weaker concentration. This species is easy to spot in the woods because the bark is an unusual silvery-yellow color, and the shaggy horizontal peelings are unique among trees.
For information on identifying birches and trees with similar leaves, see Trees with Oval Leaves.
See also Birches in Winter for information on flowers, seeds, and catkins.
