Integrated crop-livestock systems in the US corn belt

Agricultural production systems in North America have become increasingly specialized. The lack of diversification has had negative economic, biological, and environmental consequences. One alternative approach to diversify agricultural production is to integrate cash grain cropping with ruminant livestock production. Our objective was to review research applicable to development of diversified crop-livestock systems in the U.S. Corn Belt and discuss research priorities and constraints to adoption of those systems. One form of integration becoming more common in the U.S. Corn Belt occurs through contractual arrangements between spatially separated, specialized crop and livestock production farms. Less common is the spatial and temporal integration of crops and livestock on the same land base, which can occur via rotations of grain crops with perennial pastures, short rotations of grain crops with annual or short-season pastures, and utilization of grain crop residues for livestock grazing. We feel this latter model is truer to the concept of diversification. Based on published research and preliminary results from an integrated crop-livestock system project in Illinois, we suggest that integration of crops and livestock on the same land base offers tremendous potential to diversify farm ecosystems in the U.S. Corn Belt while being economically competitive and more environmentally compatible than prevailing specialized production systems. Although studies have addressed or are applicable to components of crop-livestock systems in humid-cool environments, there remains a need for systems level research and funding opportunities for addressing the complex environment-plant-animal-economic-social interactions associated with integrated crop-livestock systems.