The hunting frontier and deforestation had their own dynamics shaped by sport, trade and lumbering. But both, we have contended, were intimately related to another process of ecological transformation—the expansion of agriculture, especially of the settler, commercial variety. The farming of new crops and animals has arguably most altered the physical environment of both regions as well as having produced some of the most complex regulation. The Dust Bowl of the early 1930s which accompanied the depression on the Great Plains dominates discussion of American agriculture in mainstream environmental history. Aeolian erosion, captured in images of swirling storms blackening out the noonday sun and of fence posts topped by sand drifts, found scholarly expression in apocalyptically titled books. The epitome was Deserts on the March (1935) by the Oklahoma botanist Paul Sears.
Those few who have dealt with the topic in South Africa—where there was a similar environmental disaster in the 1930s—rely heavily on the doom-laden and portentous language of the Drought Commission. This was a key document in analysis of the ecological problems caused by settler stock farming which pictured ‘a great South African desert in the making’ (Drought Investigation Commission, 1922:2). The term was taken from the Great American Desert, marked on early-nineteenth-century maps as the region between the 98th meridian and the Rockies. Ironically, this referred to American land that had not yet been colonized—and which many thought never could be because God had made it so—as opposed to land that had been laid waste by settler occupation. (By the time of the Drought Commission’s investigations, man rather than God or nature was blamed for barren land. ) When two British colonial soil scientists, G. V. Jacks and R. O. Whyte, attempted a comparative international view of soil erosion in the 1930s, they