- Written by Clyde McMillan-Gamber Clyde McMillan-Gamber
Chestnut oak and black birch trees together dominate dry, rocky slopes and ridge tops in southeastern Pennsylvania, as well as from southern Maine and Ontario to Ohio and Delaware, and along the Appalachian Mountains to northern Georgia and Alabama.
These two species help hold down the soil against erosion and provide food and shelter for a variety of woodland wildlife. And each kind has beauties and intrigues unique to itself.
Chestnut oaks have dark, vertical ridges of rough bark divided by deep furrows. Most oaks of this type have two to four main trunks that fork close to the ground. Their broad, simple leaves are about 7 inches long, each one with rounded “teeth” on its edges.
Chestnut oaks’ pretty, oblong acorns are an inch long and chestnut-brown. And their leaves turn red, yellow, and/or brown in October.
The acorns of chestnut oaks, and other kinds of oaks, feed a host of woodland creatures, including rodents such as deer mice; gray, red, and flying squirrels; and eastern chipmunks. Squirrels and chipmunks are well known for stashing nuts in tree cavities or burying them in the ground, where some forgotten ones sprout into seedlings.
White-tailed deer, wild turkeys, and ruffed grouse feed heavily on acorns in autumn in preparation of the coming lean times in winter. Black bears gorge on acorns to put on enough fat to see them through their secluded winter’s rest.
Some individuals of the three local squirrel species build nests of broken twigs and dead leaves high in the twigs of forest trees, including chestnut oaks on rugged ridges. Those squirrel homes block wind and rain and hide the furry occupants from hawks and owls.
Black birches are known for the pleasant, wintergreen smell and taste of their twigs when crushed or chewed. Their simple, finely toothed leaves are about 3 inches long and turn yellow during October. Their bark is dark, shiny, and relatively thin and has that wintergreen fragrance.
Male catkins on black birches, and other birches, droop decoratively from the ends of twigs and sway in breezes in early spring. Those catkins dispense pollen on the wind to female flowers along the twigs. Female blossoms develop upright cones that house the maturing seeds.
When the tiny seeds are ready, the cones disintegrate, releasing those winged seeds into the wind to be scattered about.
Several kinds of woodland critters feed on parts of black birches. Mice and small, seed-eating birds ingest many winged seeds. White-tailed deer and cottontail rabbits consume the young, tender bark of twigs and trunks. And ruffed grouse eat the buds of birch twigs.
Chestnut oaks and black birches are striking trees that feed a variety of wildlife. And they have intrigues that we enjoy, including colored leaves and the smell and taste of wintergreen twigs.
Clyde McMillan-Gamber is a retired Lancaster County Parks naturalist.