Atlantic: In the 1980s, the dying red spruce trees of New England--many of them taller than eight-story buildings and more than three centuries old--furnished frightening proof of the power of acid rain. The trees were seen as a canary in the coal mine, and it was easy to imagine the ensuing consequences for the forest at large.
"Half the red spruce... are dead," Dudley Clendinen wrote for The New York Times from New Hampshire in 1983. "Some of the balsam fir are beginning to look sick. Sugar maples have...