A friend of mine told me about a hedgerow he liked to visit that was a short distance from his home. It was a spot he checked regularly with his binoculars, searching for the many birds he knew he could often find there – chickadees, woodpeckers, bluebirds, and swallows. The hedgerow held several snags, the name naturalists use for dead trees, and the birds had turned them into apartment houses.
One day, the hedgerow’s landowner began to clear it, cutting down all the trees and snags and uprooting the bushes and vines. The birds disappeared. After the hedgerow had been wiped out, a bird house on a pole appeared to take its place.
Irony is one of the traits that distinguish us from other animals.
Dozens of bird species nest in dead trees: chickadees, woodpeckers, kestrels, great crested flycatchers, tree swallows, purple martins, owls, wood ducks, and the much-sought-after eastern bluebird. Even the eagle and osprey need the tops of large, dead trees in which to build the big platforms of sticks that constitute their nests.
These are the birds we most love. They are why we put up bluebird boxes in our yards, why we spend good money for purple martin condominiums, why we pay taxes to fish and wildlife departments to mount wood duck boxes in our marshes and to erect osprey platforms near our ponds and lakes. The birds take readily to the substitute accommodations because dead trees, their natural nesting structures, are in short supply.
Birds aren’t the only creatures that need dead trees. Bats, flying squirrels, and raccoons find shelter in their cavities. The pupae of butterflies and other insects winter under their loose bark. Mushrooms thrive on their rotting roots. Ants turn them into castles.
In fact, the dead tree just might be the most rare and valuable tree in the landscape.
Vermont and New Hampshire were largely deforested during the first half of the nineteenth century as woodlands were converted to pastures. While more than three-quarters of the two states is now reforested, these new forests, in the grand scheme of things, are roughly middle-aged. Death rates are low, and large snags are less common in these forests.
Our oldest trees today are those that either avoided the teeth of settlers’ saws – those that marked boundaries, provided shade for a house or in a cow pasture, or grew in inaccessible places – or, more commonly, those that started out as saplings later in the eighteenth century.
Snags are also relatively rare because there is something about a dead tree that bothers us humans. Some of this worry is justified. Dead trees near our homes can be hazardous to the car, the roof, and the kids. There may be no option but to cut them down.
But a dead tree that is well away from valuable property or the kids’ swing is a danger to no one, yet we often cut them down for no good reason. Some people believe, mistakenly, that they breed diseases and pests. Perhaps they are cut down because of an obsession with neatness, and a snag on our property is regarded as an affront to our tidy reputations. Maybe we cut them down because a dead tree is dead, and we abhor things that remind us of our mortality. Or perhaps we cut them down because we’re looking for wood for the woodstove, and dead and dying trees seem somehow better to cut than trees in the prime of life.
If we select against dead and dying trees, however, we’re also selecting against all the plants and animals whose livelihood depends on these trees.
Over the last few years, on my commute to work, I have passed by a cottonwood in the prime of its death and watched as nature slowly whittles it away. Perhaps it died of old age or a lightning strike. Whatever the cause of death, one year it stopped sprouting leaves. Then the tiny twigs and branches dried up and were stripped away in winter by wind and snow and in spring by crows and mourning doves needing twigs for their nests. Later the larger branches were excavated by nesting flickers. Recently a pileated woodpecker has drilled oblong holes in the trunk to reach its favorite food, carpenter ants, which are turning the wood into sawdust.
In life this tree must have been a beauty, rising to nearly 75 feet, its massive crown touching the sky and spreading a pool of shade on the ground below. In death it is beautiful still, a refuge and a sanctuary for many living creatures. They say beauty is in the eye of the beholder. If a dead tree is ugly in your eyes, perhaps it is time to change your view.