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crop rotation, agricultural economics


Cropping systems in the United States and throughout much of the world have moved toward shorter and less diverse rotations during the last half of the twentieth century. However, as we approach the new millennium, there is growing concern about the ecological sustainability of monocultures and such narrow rotations as the com-soybean rotation. Problems of pest control, crop disease, groundwater contamination from chemical pesticides and fertilizers, and soil erosion are proving to be very difficult when crop rotation systems lack diversity. "Silver bullet" technologies sometimes buy time, but without diversity, new ecological problems soon replace the problem just "solved" with the latest pest-resistant crop variety or chemical pesticide. Concerns about the lack of crop system diversity lead to questions about how public policies might be used to alter agriculture's path. Answering those questions requires a clear understanding of how policies and other economic forces have influenced crop systems in the recent past. We have attempted to gain some of that understanding through a case history of one region within North America's agricultural heartland. The results of our historical analysis are reported in this research report. In a companion paper, we will examine recent policy changes embodied in the 1996 Federal Farm Bill (the Federal Agriculture Improvement and Reform Act) and the potential implications of those changes for future crop system diversity.


Economics Research Report No. 99-2