It is impossible to imagine the Great Depression in the United States without envisioning the era's environmental tragedies. Seared onto the national memory by novelists, filmmakers, and government photographers, portraits of uprooted and impoverished people mingle with images of scarred land, abandoned farms, and swollen rivers. Dust clouds darken the Great Plains and move threateningly toward the nation's capital. A lone, broken windmill looms over parched cattle and crumbling fields. Migrants, fleeing dirt and drought, trek along Route 66 to California's unwelcoming fruit orchards. A black sharecropper stands helpless beside the deepening gully that has stolen his farm's precious topsoil. Clutching their few belongings, refugees race the rising water and watch from a nearby hill as the river claims their homes.

These images of environmental disaster are matched by equally familiar stories of state-sponsored environmental renewal. The president dedicates a new national park with a stirring address. Young men receive jobs battling soil erosion, replanting damaged forests, and constructing campgrounds. The federal government builds new farms for some and manages migrant camps for others. High dams rise along the Tennessee and the Colorado. “Your power is turning our darkness to dawn,” sings Woody Guthrie, “so roll on, Columbia, roll on.” Despite the indisputable importance of these episodes, however, historians have never made them central to their interpretations of the New Deal, nor to their analyses of American political development.