Center pivots can be used to achieve variable-rate chemigation — applying variable dosages of agricultural chemicals through the irrigation system within the same field.
We present three items in our paper:
1) Equations specifying how a center pivot and the chemical injection pump can be operated to vary chemical dosages
2) A software tool to assist with variable-rate chemigation calculations
3) Field test findings from Brule, Nebraska, that demonstrate the accuracy of a commercial, uncustomized variable rate chemigation system.
Publication: Lo, T.H., D.R. Rudnick, and T.M. Shaver (2019). Variable-Rate Chemigation via Center Pivots. J. Irrig. Drain Eng. 145 (7): 04019012.