Several years ago, after Thanksgiving dinner at my parents’ house in Vermont, lightning struck a backyard maple tree. There was a ferocious crack and the darkness outside the kitchen windows briefly turned day-bright. It wasn’t until spring that we knew for certain the tree was dead.

This maple was a youngster, its trunk the diameter of a salad plate. Were its life not cut short by catastrophe, the tree might have lived 300 years. But death by disaster is surprisingly common in trees. Som