COAL, NATURAL gas, petroleum. Thoughtlessly we call these substances “fuels”—fuels to burn for creating pleasant climates inside homes and offices; fuels to power appliances and engines. For years, like nearly everyone, I never thought beyond our mere use of these things. I neglected to consider their role in the Earth’s wider economy.
This all changed when my family moved to a Wisconsin peatland in 1972. Since then, conducting research there with my graduate students has produced four decades of discovery.
For thousands of years, wetland plants and algae in a bay of glacial Lake Waubesa took carbon dioxide from the atmosphere. They transformed it by photosynthesis into the carbon structure of life, eventually adding their remains, page upon page, to the accumulating peat. Eventually, this peat filled the bay for an area more than a mile long, reaching a depth of 95 feet at the present lake edge. When first I walked here, I saw the vibrant surface of plants and wetland creatures; now, in my mind’s eye, I also see the deep-layered remains of creatures below.
Also standing and walking here (much more gracefully than I) are sandhill cranes. These stately creatures, as conservationist Aldo Leopold observed, “stand, as it were, upon the sodden pages of their own history.” Elsewhere, the sodden pages of peat deposits have been cut over the ages to be dried for fuel. The early Romans saw this practiced by conquered peoples of northern and western Europe. Peat was also used as fuel in Ireland, Scotland, and northern Europe after forests were cleared for agriculture. And peat is the precursor of coal, transforming under geologic pressure into brown coal, bitumen, bituminous coal, and anthracite.