IN environmental parlance, the ecotone is the zone where two habitats merge, that threshold where water meets the shore, where the forest comes to meadow, or where woodland ends at a cultivated lawn. It is the edge habitat where everything — soil content, vegetation, moisture, humidity, light, pollination — changes. It’s also where species from both sides converge, rendering it a place of complex interaction and diversity.
All of which makes it a good place to work. My small office here in the Hudson Valley of New York is situated at the edge of our yard, where the woods of oak, maples and hickories meet the brambles, the rye grass and timothy. Things are always happening here: White-tailed deer wander out from the woods foraging for something to eat, and wild turkeys often parade through the long grass. Once, at dusk, I saw a coyote slipping through the trees, and for a few brief moments two winters ago, a small gray bobcat. And one morning last summer I was astonished to see a black bear amble out from the trees.
The view from my window is of a place of constant change and unexpected appearances. Such a landscape can be helpful when you’re trying to distill a nebulous idea into a handful of words. It could be nothing more than a ring-necked pheasant pecking at the dry leaves, its iridescent green feathers picking up the glint of afternoon light, but a glance outdoors is enough to remind me of the intensity and complexity in these places of transition, where one thing manages to become another.
Aldo Leopold, forester, writer and dean of American wildlife conservation, articulated the idea of the edge effect in his 1933 classic, “Game Management.” Observing how different species search out different peripheries, he wrote that the grouse hunter looks to the edges of the woods “with its grape tangles, haw-bushes, and little grassy bays,” while the quail hunter “follows the common edge between the brushy draw and the weedy corn,” and the deer hunter “the edge between the oaks of the south slope and the pine thicket of the north slope.”
“We do not understand the reason for all of these edge-effects,” he wrote, “but in those cases where we can guess the reason, it usually harks back either to the desirability of simultaneous access to more than one environmental type, or the greater richness of border vegetation, or both.”
Humans, too, have some primal appreciation for this piece of environmental real estate. We seem to know that the edge is where the action is, or the place you push things to for the best results. When you understand the periphery’s purpose and significance in ecology, it gives you another way to understand different edges in human society and how their energy is created, whether you are talking about the borders between diverse populations in urban communities or more abstract reflections on how ideas intersect and are cross-pollinated.
In an essay about ethnic identity, the historian and essayist Tony Judt wrote about his preference for the edge as “the place where countries, communities, allegiances, affinities and roots bump uncomfortably up against one another.” Margins and edges, he suggested, offer us “a decidedly advantageous perch.”
And it occurs to me now, as we edge into a new year, that time has an ecotone of its own, some thin cusp where before meets up with after. Because surely the edge effect can be a circumstance of chronology as well as one of place. And surely the way the months, seasons, years brush up against one another can produce a similar influence of change, diversity, vitality.
Perhaps it is possible to imagine year’s end as having some temporal edge effect, to see it as the place where desire and expectation intersect with actuality. And to look at this time of year as an interval during which one is suddenly more attentive to that friction between the finished and the unfinished, the energy that lies between the done and the undone.
If adjacencies of terrain nurture biodiversity, maybe this juncture of years can generate similar sudden sightings of unexpected possibilities. How many minutes, hours, days are equal to a few feet of wild grass and bramble? And who knows what could show up during that time? It could be anything. The bears are asleep now, but it could be a turkey flapping in the brush, a gray squirrel practicing its aerials, or a coyote slipping by so elusively that all I’ll ever notice are its prints in the snow.
Akiko Busch is the author of “The Incidental Steward: Reflections on Citizen Science.”