Established in 1896 by Professor J.F. Duggar, the Old Rotation at Auburn University is the oldest continuous cotton experiment in the U.S., the third oldest continuous field crop experiment in the U.S., and the first experiment to demonstrate the benefits of rotating cotton with other crops to improve yields and use nitrogen-restoring legumes in a cotton-production system. It continues to document the long-term effect of these rotations in the same soil. The Old Rotation consists of 13 plots on 1 acre of land, with each plot devoted to a different crop rotation of cotton with corn, summer legumes, winter legumes, and fertilizer nitrogen.