Abstract

Edge Effect Capitalism: The North American Fall Line in the Longue Durée

Interstate-95 is the longest north-south highway in the United States, and about sixty percent of it runs directly along the North American fall line between New York City and North Carolina. Before the windows of interstate vehicles, centuries of human experience unfold. That the highway aligns closely with the geological feature is no coincidence. The North American fall line is an “ecotone,” an edge between environmentally distinct regions. It is the linear zone where the rolling hills of ancient stone comprising the Piedmont region adjoin the geologically-young flatlands of the Tidewater region. In the absence of human intervention in the landscape, the fall line would be invisible from the distant vantage of space. Yet today, when one observes eastern North America as translated by powerful Earth-observation satellite technology, the fall line appears as an outstanding feature, a contiguous grey band of buildings, city blocks, and highway miles bearing seemingly little relation to the underlying geology but following it nevertheless across the landscape with dogged regularity. Why? Environmental edge effects of the fall line have attracted and sustained human activity and the accumulation of capital atop of the geological feature over the longue durée. As an ecotone, the fall line produces “edge effects,” the structural influence of dissimilar environments adjoining and interacting. A notable edge effect is increased resource endowment. Along the fall line the different resources available in the Piedmont and the Tidewater regions, in the upland and the lowland environments, were both equally accessible and exploitable. As one nineteenth-century observer of a fall line location put it, “all the riches of nature are brought together in this spot, but without confusion.” Fall line edge-effect resource density has had consequences across long stretches of time. Through four case studies, this study show how successive generations exploited fall line edge effects to accumulate capital, and why, even as technology changed and industries rose and fell, capital accumulation continued apace upon the fall line.