Diagram of Old RotationThe Old Rotation consists of 13 plots on exactly 1 acre of land. Each plot is 136 feet long by 21.5 feet wide with a 3-foot border between each plot. Originally, each plot was a different combination of crop rotation with timing of fertilizer P and K applications. Over the years, treatments have changed slightly (Table X); today, the timing of P and K applications is no longer critical since most plots test high in P and K. The treatments today can be grouped into 3 crop rotation systems.



Cotton Every Year


     No N and no cover crop

1, 6

     No N fertilizer with a winter legume cover crop

2, 3, 8

     120 lb. N/acre and no cover crop


2-Year Cotton-Corn Rotation


     +Winter legume cover crop

4, 7

     + Winer legume cover crop plus N fertilizer

5, 9

3-Year Rotation (cotton-legume-corn-wheat-soybean)

10, 11, 12