Associating conservation/production patterns in US farm policy with agricultural land-use in three Iowa, USA townships, 1933–2002

Abstract

Agricultural policy objectives in developed nations include counteracting overproduction, increasing economic and social well-being, and environmental protection. Such policies, however, often work at cross-purposes. While vast financial resources have been invested in farm programs, little research connects historic trends in agricultural policy with land-use patterns in agricultural landscapes. We connect the legislative history of US farm bills with land-use decisions as observed on the historical agricultural landscape in three townships in Iowa, USA, 1933–2002. With a high proportion of agricultural land, increasing biofuels development, and high participation in federal conservation programs, Iowa presents an ideal case study to explore the relationship between policy and historical land use. Using data from the US Census of Agriculture and historical aerial photography, we conduct our analysis within a framework that identifies alternating eras of US farm policy in terms of legislative focus on conservation vs. production. We describe the impact of US farm policy on the following indicators: maize and soybean area, production, and productivity; hectares in idled land, pasture, and hay ground; and adoption of soil conservation practices. Patterns of agricultural and conservation land use support the idea of alternating conservation–production eras of US farm policy. Three important patterns emerge: (1) despite reductions in maize hectares that correspond with conservation-oriented policy eras, supply management policies have failed to control maize production due to increased productivity; (2) as pasture and hay hectares decline, government set-aside programs are increasingly important for perennial vegetation within agricultural landscapes; and (3) although soil conservation practices have generally increased as agricultural land use has intensified, persistent links between poor environmental quality and farm programs suggest that implementation alone will not achieve environmental quality goals. Environmental improvement likely requires a shift from policies focused on the quantity of commodities produced to policies focused on pattern and process of production in multifunctional agricultural landscapes, and we discuss how policies that promote extensification abroad might inform domestic agricultural policy reform.