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Precision irrigation or chemigation using mechanized irrigation systems such as center pivots or lateral moves requires accurate and real-time knowledge of the irrigation system's field location. A GPS receiver mounted on a center pivot or lateral move has the potential to increase the accuracy of these position estimates. Differentially corrected GPS receivers have become more affordable (less than $200 US) and it has become more feasible to use them for reporting field position of mechanized irrigation systems. Although these low-cost differentially corrected receivers have been shown to have accuracies of 95% less than 2.1 meters in previous experiments in the panhandle of Texas, the remaining 5% of the reported points gave errors greater than 6 meters. These errors are large enough to present problems for site-specific irrigation. It was hypothesized that the errors from an additional GPS receiver in a known, stationary location could be used to correct the positioning estimates of the receiver mounted on a moving irrigation system and thereby improve the accuracy sufficiently for use with precision irrigation or chemigation. This was tested by placing two similar low-cost receivers in stationary locations and correlating the errors in the North- South and East-West directions. The r2 values of the linear regression lines were very small, showing that almost no correlation existed between the errors of these two receivers. This demonstrated that the integration of an additional, stationary low-cost GPS receiver will not significantly improve positioning estimates of GPS receivers mounted on moving irrigation systems.