A commercially available on-the-go soil pH sensor measures and maps subsurface soil pH at high spatial intensities across managed landscapes.  The overall purpose of this project was to evaluate the potential for this sensor to be used in agricultural fields. The specific goals were to determine and evaluate 1) the accuracy with which this instrument can be calibrated, 2) the geospatial structure of soil pH measurements, and 3) interpolation quality.  The study was conducted at a research farm in central Kentucky. Soil pH sensor measurements were collected and georeferenced. Prediction datasets were created from measurements collected along parallel passes separated by 12-m.  Validation measurements were collected along passes that were approximately perpendicular to direction of the prediction data set measurements with passes separated by 42.67-m. Calibration datasets were collected with a hand probe (10-cm depth). Semivariograms were calculated with SAS (Cary, NC) and modeled visually. Simple relationships were strong between sensor and laboratory measurements including soil water pH (r²= 0.87), salt pH (r²= 0.85), and SMP buffer pH (r²= 0.84). The data were well structured spatially (i.e., relative structural variability = 78.7%; range of spatial structure = 31-m). Kriging prediction errors with the validation dataset were larger than desired (i.e., rmse = 0.418; r² for the relationship between predicted and measured values = 0.52). The data suggest that the on-the-go pH sensor has potential to be a useful tool in agricultural fields in Kentucky.