Native Americans had many other uses for Betula papyrifera, too, including
food, tea, sleds, snowshoes, mats, baskets, and containers, as well as utensils,
spears, arrows, bows, and baby carriers. In the old days, Norwegians roofed
houses with birch bark and the Sami made clothing out of it. Today, the tree is
used medicinally for many ailments. Its sap is used to make beer, wine, syrup,
and vinegar, and to treat leather. Its oils are used to repel insects, and the bark
has fungicidal properties. In addition, it is used commercially for plywood and
veneer, furniture, fuel, and as pulpwood.
Most paper birches are mature when about 70 years old, but by that time, a
typical tree has cast many millions of light, winged seeds – at the rate of nine
million a year during its 30 most productive years.
The seeds begin ripening in August and are dispersed over several months,
through November. An important food for common redpolls and pine siskins,
they are also eaten by voles, shrews, chickadees, purple finches, sparrows, and
grouse. Grouse eat the buds and catkins in winter. Young birch stands provide
cover and browse for moose, deer, and snowshoe hare. Beaver and porcupines
eat the bark of somewhat larger trees.
Stressed trees are particularly vulnerable to attack by the bronze birch borer
(Agrilus anxius), the most serious insect pest of paper birch. Woodpeckers
search out and eat the larvae, but the sapsucker member of this family may
simultaneously be guilty of stressing birch trees by drilling rows of sap oozing
holes. It is not hard to stress a birch, for it is generally a shallow-rooted tree,
with most of its roots in the upper 24 inches of soil. Lacking a taproot, it is
susceptible to drought and easily injured by heavy equipment.
Nearly every New England calendar includes a photo of a clump of snowy-white birches gleaming in the sun, but it’s hard to argue that an undue amount
of praise has been accorded this species. Its astonishing whiteness, its graceful
ascent into the canopy, the usefulness of its bark, the beauty of its wood, and
its value as food for birds and other wild animals easily earn the admiration
heaped upon it. The trees themselves lean out over lakes and ponds as though
to better admire their own white limbs reflected in the still water.