The Prairie, What Survived the Plow

Before the homesteaders broke the sod, the eastern half of South Dakota was one of the most biologically complex landscapes on earth. The mixed-grass prairie held hundreds of species of grasses and forbs in a single square yard of ground. The root systems went down six, eight, ten feet, a subterranean architecture that had been building for ten thousand years, since the glaciers released the land and the grasses moved in behind them. Bison once numbered in the tens of millions across the Great Plains. Prairie dogs built towns covering tens of thousands of acres. Pronghorn and elk grazed the uplands; beaver dammed every stream.

The homestead era and the Dust Bowl between them broke most of that. Today only a small fraction of the native tall-grass prairie remains. The soil that had taken ten thousand years to build had, in many places, blown away in a decade.

What survived did so in corners: the steep draws too rocky to plow, the reservation lands that never went through the homestead mill, the long narrow strips along fence lines. The Nature Conservancy and the National Park Service have been working in recent decades to stitch those remnants back together in the Badlands and at other prairie preserves. The bison have returned to several of those sites. The prairie dog towns are coming back, slowly, dragging the black-footed ferrets and the burrowing owls and the swift foxes behind them in a chain of dependencies that took the grassland millennia to assemble and about seventy years to dismantle.