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82  A Landscape of Chance A Landscape of Chance  I believe it was the silence that woke me, an unnatural quiet in the silvery half-light before dawn, the hour of wood thrushes’ songs. As I rose through the clouds of sleep, their absence grew alarmingly real. An Adirondack morning usually arrives to the accompaniment of veeries’ and robins’ songs, but not on this day. I rolled over to look at the clock. 4:15. The light outside suddenly shifted from silver to steel and thunder grumbled in the distance. The aspens turned up their leaves to flutter stiffly in the stillness, giving their rain call in the silence left by the birds. They must be hunkered down, I thought, in anticipation of the rain. Around here they say, “Rain before seven, done by eleven.” I’d probably get to go canoeing after all. I snuggled back under my covers to wait it out. That’s when the pressure wave hit the cabin like an axe against a tree. Jumping out of bed, I ran to shut the cabin door, which had been suddenly flung open by the force of the wind. The cabin windows looked out onto a lake frothing and churning like the ocean, under a sky which had turned a sickly shade of green. The paper birches on the shore were bent nearly horizontal, their thrashing gyrations caught in the strobe of lightning, white on white, as a curtain of electricity advanced across the lake. The big pine over the porch began to wail and the windows seemed to press ominously inward. I herded my small daughters to the back of the cabin. We cowered in anticipation of shattered glass and splintered pine, small and speechless before the storm. The thunder rolled and rolled, like a long freight train roaring by, then leaving silence in its wake. The sun rose over a placid blue lake. But still there were no birds. Nor would there be for the rest of that summer. On July 15, 1996, the Adirondacks woke to a landscape battered by the most powerful storm ever recorded east of the Mississippi. Not a tornado, but a microburst, a wall of convective thunderstorms riding a pressure wave off the Great Lakes. Trees were snapped and uprooted in A Landscape of Chance  83 swaths of blowdown that took every tree. Campers were pinned in their tents and hikers stranded in the backcountry, where trails disappeared under piles of timber thirty feet high. Helicopters were dispatched to carry them to safety. In a single hour, vast tracts of shaded woodland became a jumble of torn trees and upturned soil, exposed to the glare of the summer sun. Such land-clearing events are rare, but forests exhibit remarkable resilience in the face of disaster. I’m told that the Chinese character for catastrophe is the same as that which represents the word opportunity. And the blowdown, while catastrophic, presented opportunity for many species. Aspens, for example, are perfectly adapted to take advantage of periodic disturbances. Quick growing and short lived, aspens produce light wind-blown seeds that sail away on cottony parachutes. In order to travel fast and far, aspen seeds come with minimal baggage. They can live for just a few days, and will die unless they germinate. An aspen seed that lands on an undisturbed forest floor hasn’t a chance of success. Its tiny rootlet, the key to self-sufficiency, cannot penetrate the thick leaf litter and the dense canopy shades out the sun it needs. But, in the aftermath of the storm, the forest floor has been churned up into a tumult of logs and soil thrown up by uprooted trees. In the full sun, on clean mineral soil, the aspen seedlings will be the first to colonize the devastation. Storms such as this one come perhaps once in a century, but the wind blows nearly every day, rocking the canopy trees and weakening their hold in the soil. The predominant cause of tree mortality in the northern deciduous forest is windthrow. Gravity always wins in the end. In frequent storms, or under winter’s load of ice, individual trees come crashing down with great regularity, like pendulum strokes of the ecological clock. Even on a calm day, you can sometimes hear a tree groan and lean with a whoosh to the ground. The fall of a single tree punches a hole in the canopy and a shaft of light follows it to the forest...

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