The “Old Rotation”(c. 1896) is the oldest continuous cotton experiment in the world and the third oldest field crop experiment on the same site in the United States*. This rotation also includes rotations with corn, soybean, and small grains and includes winter cover crops, mainly winter legumes. It was placed on the National Register of Historical Places in 1988.
The “Old Rotation” was one of the first experiments to demonstrate and document the value of rotating cotton with other crops and including nitrogen-restoring legumes in the system. Information from this test provided evidence that rotation with legumes could sustain and actually improve yields of cotton and corn in Alabama soils. Data from this experiment have been the source of numerous scientific, popular, and educational publications on cotton production, cover crops, soil fertility, and sustainable agriculture. Because only minor changes have been made in the cropping systems, it continues to document the effect of these systems on productivity, soil and environmental quality, and sustainable agriculture. The “Old Rotation” consists of 6 cropping systems in 13 plots on 1 acre of a Pacolet fine sandy loam (Fine, kaolinitic, thermic Typic Kanhapludults) on the campus of Auburn University in East Central Alabama. The experiment sets on the junction of the Southern Piedmont and the Gulf Coastal Plain soil physiographic regions.
*Older experiments are the “Morrow Plots” at the University of Illinois and the “Sanborn Field” at the University of Missouri-Columbia.