What We Owe Our Trees

The woods I know best, love best, are made of Northern hardwoods, sugar maple and white ash, timber-tall; black and yellow birch, tiger-skinned; seedlings and saplings of blighted beech and striped maple creeping up, knock-kneed, from a forest floor of princess pine and Christmas fern, shag-rugged. White-tailed deer dart through softwood stands of pine and hemlock, bucks and does, the last leaping fawn, leaving tracks that look like tiny human lungs, trails that people can only ever see in the snow, even though, long after snowmelt, dogs can smell them, tracking, snuffling, shuddering with the thrill of the hunt and noshing on deer scat for dog treats. I make lists of finds, two-winged, four-footed, and rolling: black-throated green warblers and blue-headed vireos, porcupines and salamanders, tin cans and old tires, deer mice and fisher cats, wild turkeys and ruffed grouse, black bears and, come spring, their tumbling, potbellied, big-eared cubs.

Even if you haven’t been to the woods lately, you probably know that the forest is disappearing. In the past ten thousand years, the Earth has lost about a third of its forest, which wouldn’t be so worrying if it weren’t for the fact that almost all that loss has happened in the past three hundred years or so. As much forest has been lost in the past hundred years as in the nine thousand before. With the forest go the worlds within those woods, each habitat and dwelling place, a universe within each rotting log, a galaxy within a pine cone. And, unlike earlier losses of forests, owing to ice and fire, volcanoes, comets, and earthquakes—actuarially acts of God—nearly all the destruction in the past three centuries has been done deliberately, by people, actuarially at fault: cutting down trees to harvest wood, plant crops, and graze animals.

The Earth is about four and a half billion years old. By about two and a half billion years ago, enough oxygen had built up in the atmosphere to support multicellular life, and by about five hundred and seventy million years ago the first complex macroscopic organisms had begun to appear, as Peter Frankopan reports in “The Earth Transformed” (Knopf), an essential epic that runs from the dawn of time to, oh, six o’clock yesterday. In his not at all cheerful conclusion, looking to a possibly not too distant future in which humans fail to address climate change and become extinct, Frankopan writes, “Our loss will be the gain of other animals and plants.” An upside!

The first trees evolved about four hundred million years ago, and pretty quickly, geologically speaking, they covered most of the Earth’s dry land. A hundred and fifty million years later, during a mass-extinction event known as the Great Dying, the forests perished, along with nearly everything else on land and sea. Then, two million years after that, the supercontinent broke up, a seismic process whose consequences included depositing oil, coal, and natural gas in the places on the planet where they can still be found, to our enrichment and ruination. The trees returned. The ginkgo is the oldest surviving tree species, its fan-shaped leaves unfurling lime green in spring and falling, mustard yellow, in autumn.

The first primates showed up about fifty-five million years ago, in the rain forest. They lived in the trees. Our ancestors began dividing from apes—began, slowly, coming down from the trees—about seven million years ago; the genus Homo branched off four million years later; and Homo sapiens began wandering around the understory somewhere between eight hundred thousand and two hundred thousand years ago, although exactly when is apparently a matter of fierce debate, which seems right, since humans are such a contentious, Neanderthal-killing lot. Here’s how Frankopan, a professor of global history at Oxford, puts it: “Like rude house guests who arrive at the last minute, cause havoc and set about destroying the house to which they have been invited, human impact on the natural environment has been substantial and is accelerating to the point that many scientists question the long-term viability of human life.” Climate change contributed to the extinction of Neanderthals about thirty-five thousand years ago, but humans, instead of dying out, migrated to different climates, or found other ways to survive, which generally involved controlling fire and burning fallen sticks and branches for heat and to cook otherwise hard-to-digest food, or making axes to cut down trees, whose wood could be used to build shelters and, later, fences for animals. They cut and felled. Knopf printed about twenty thousand copies of Frankopan’s seven-hundred-page book on paper made from trees. I read it sitting in a house built of pine in a chair made of maple at a desk made of oak holding a pencil made of cedar. They cut and felled. The wood in my woodstove is yellow birch, burning, bark curling.