hardwood seedlings an open sky to fill with their canopies.
But even if you don’t know a birch from a beech, you can’t miss seeing it around knee-height, camouflaged by fallen leaves and lichens, or wrapped in green brambles. Someone has been here. The low stone walls that crisscross the forests of Maine, Vermont, New Hampshire, Massachusetts, Connecticut, and upstate New York reveal that humans once staked boundaries here. An 1871 fencing census, writes Connecticut geologist Robert Thorson, showed at least 240,000 miles of handmade stone walls east of the Hudson River—enough to reach to the moon.
As the last glaciers of the Pleistocene advanced, stones were ripped from granite outcroppings, then dropped as they melted back. Some lay on the surface; some were ground into the subsoil, to be periodically heaved up by frost. All had to be cleared along with trees so that transplanted European farmers could start over in a New World. The stones and boulders they moved marked the borders of their fields and penned their animals.
So far from large markets, raising beef wasn’t practical, but for their own use New England’s farmers kept enough cattle, pigs, and dairy cows that most of their land was pasture and hay fields. The rest was in rye, barley, early wheat, oats, corn, or hops. The trees they downed and the stumps they yanked were of the mixed hardwood, pine, and spruce forests we identify with New England today—and we do, because they’re back.
Unlike almost anywhere else on Earth, New England’s temperate forest is increasing, and now far exceeds what it was when the United States was founded in 1776. Within 50 years of U.S. independence, the Erie Canal was dug across New York State and the Ohio Territory opened—an area whose shorter winters and loamier soils lured away struggling Yankee farmers. Thousands more didn’t bother to return to the soil after the Civil War, but headed instead into factories and mills powered by New England’s rivers—or headed west. As the forests of the Midwest began to come down, the forests of New England began coming back.
The unmortared stone walls built by three centuries of farmers flex as soil swells and shrinks with the seasons. They should be part of the landscape for a few more centuries, until the leaf litter turns to more soil and buries them. But how similar are the forests growing around them to what was here before the Europeans arrived, or the Indians before them? And untouched, what would they become?
In his 1980 book
We now know that many of the allegedly pristine landscapes of North and South America were actually artifacts, the result of enormous changes wrought by humans that started with the slaughter of megafauna. The first permanent Americans burned underbrush at least twice a year to make hunting easier. Most fires they set were low-intensity, meant to clear brambles and vermin, but they also selectively torched entire stands of trees to shape the forest into traps and funnels to corner wildlife.
The coast-to-Mississippi treetop traverse would have been possible only for birds. Not even flying squirrels could have managed it, because it took wings to cross large swathes where forest had been thinned to parkland or razed completely. By observing what grew after lightning opened clearings, paleo-Indians learned to create berry patches and herb-filled meadows to attract deer, quail, and turkeys. Finally, fire allowed them to do exactly what the Europeans and their descendants later came to do on such a grand scale: They farmed.
Yet there was one exception: New England, one of the first places where colonists arrived to stay, which may partly explain the familiar misconception of an entire virgin continent.
“There’s now an understanding,” says Harvard ecologist David Foster, “that precolonial eastern America had an agriculturally-based, maize-dependent large population with permanent villages and cleared fields. True. But that’s not what we had up here.”
It is a delicious September morning in deeply wooded central Massachusetts, just below the New Hampshire border. Foster has paused in a stand of tall white pines, which just a century earlier was a tilled wheat field. In their shady understory, little hardwoods are sprouting— maddening, he says, to timbermen who came after New England farmers had departed for points southwest and who thought they had a ready-made pine plantation.
“They spent decades of frustration trying to get white pine to succeed itself. They didn’t get that when you cut down the forest, you expose a new forest that rooted in its shade. They never read Thoreau.”
This is the Harvard Forest outside the hamlet of Petersham, established as a timber research station in 1907 but now a laboratory for studying what happens to land after humans no longer use it. David Foster, its director, has managed to spend much of his career in nature, not classrooms: at 50, he looks 10 years younger—fit and lean, the hair falling across his forehead still dark. He bounds over a brook that was widened for irrigation by one of the four generations of the family who farmed here. The ash trees along its banks are pioneers of the reborn forest. Like white pine, they don’t regenerate well in their own shade, so in another century the small sugar maples beneath them will replace them. But this is already a forest by any definition: exhilarating smells, mushrooms popping through leaf litter, drops of green-gold sunlight, woodpeckers thrumming.
Even in the most industrialized part of a former farm, a forest resurges quickly here. A mossy millstone near a tumble of rocks that was once a chimney reveals where a farmer once ground hemlock and chestnut bark for tanning cowhides. The mill pond is now filled with dark sediment. Scattered firebricks, bits of metal and glass, are all that remain of the farmhouse. Its exposed cellar hole is a cushion of ferns. The stone walls that once separated open fields now thread between 100-foot conifers.
Over two centuries, European farmers and their descendants laid bare three-quarters of New England’s forests, including this one. Three centuries more, and tree trunks may again be as wide as the monsters that early New Englanders turned into ship beams and churches—oaks 10 feet across, sycamores twice as thick, and 250-foot white pines. The early colonists found untouched, huge trees in New England, says Foster, because, unlike other parts of precolonial North America, this cold corner of the continent was sparsely populated.
“Humans were here. But the evidence shows low-density subsistence hunting and gathering. This isn’t a landscape prone to burning. In all New England, there were maybe 25,000 people, not permanently in any one area. The postholes for structures are just two to four inches across. These hunter-gatherers could tear down and move a village overnight.”
Unlike the center of the continent, says Foster, where large sedentary Native American communities filled the lower Mississippi Valley, New England didn’t have corn until AD 1100. “The total accumulation of maize from New England archeological sites wouldn’t fill up a coffee cup.” Most settlements were in river valleys, where agriculture finally began, and on the coast, where maritime hunter-gatherers were sustained by immense stocks of herring, shad, clams, crabs, lobsters, and cod thick enough to catch by hand. Inland camps were mainly retreats from harsh coastal winters.
“The rest,” says Foster, “was forest.” It was a human-free wilderness, until Europeans named this land after their own ancestral home and proceeded to clear it. The timberlands the Pilgrims found were the ones that emerged in the aftermath of the last glaciers.
“Now we’re getting that vegetation back. All the major tree species are returning.”
So are animals. Some, like moose, have arrived on their own. Others, like beavers, were reintroduced and have taken off. In a world without humans to stop them, New England could return to what North America once looked like from Canada to northern Mexico: beaver dams spaced regularly on every stream, creating wetlands strung like fat pearls along their length, filled with ducks, muskrats, willets, and salamanders. One new addition to the ecosystem would be the coyote, currently trying to fill the empty wolf niche—though a new subspecies may be on the rise.
“The ones we see are substantially larger than western coyotes. Their skulls and jaws are bigger,” says Foster, his long hands describing an impressive canine cranium. “They take larger prey than coyotes in the West, like deer. This probably isn’t sudden adaptation. There’s genetic evidence that western coyotes are migrating through Minnesota and up across Canada, interbreeding with wolves, then roaming here.”
