Autumn

There is much more to the fall season than meets the eye, as Marchand demonstrates in this gracefully written introduction to the science of autumn. The spectacular display of leaves changing colors occurs in concert with hidden processes, as plants redirect their metabolism toward dormancy and protection, synthesizing proteins and minerals and storing them in stems and roots. Much about autumn remains mysterious, even improbable--the deathlike hibernation of animals, the migration over thousands of miles of birds, ladybeetles, butterflies, moths. Fall migrants include the caribou of Canadian and Alaskan forests, which take a long walk south, it seems, to escape millions of blood-sucking and parasitical insects. Marchand, visiting professor of conservation biology at Colorado College, deftly synthesizes the latest scientific research on migrations, the ecology of ponds and lakes, plants' seed-dispersal strategies, the food-hoarding habits of squirrels, foxes and birds. As counterpoint to his detailed text, he includes excerpts from the meticulous yet lushly lyrical writings of early naturalists such as Thoreau, Martha McCulloch Williams, Charles Abbott and John Burroughs. His eye-opening study contains many surprising or little-known facts. For example, ""Indian summer"" originally referred to the hazy, milder days of autumn--a haze attributed to Native Americans' burning of prairie grasses, but also resulting from the immense annual production of forest litter, organic matter that produces light-scattering aerosol particles. And the secretive, highly adaptive vole, widespread creature of fields and forests, balances energy so well that it manages to avoid hibernation and remains active year-round. Marchand's own 36 black-and-white photographs focus on autumnal processes that bind living creatures in a cycle of birth, death and renewal. (July)