Abstract: A site-specific farming system for performing work on an agricultural field while soil compaction conditions of the field are being recorded includes a vehicle such as a tractor equipped with an element carrying farming tools for working the field, such as a plow. Sensors, including hitch load pins and/or strain gauge type sensors, detect the load on the tools due to the soil compaction. A location signal generation circuit generates signals relating to the location at which the force signal is sampled. The force data is correlated with the locations at which the force was sampled. The correlated data is stored in a memory. The user interface may include re-definable switches. A display may show a field map including the soil condition values, including soil compaction, and other sensed data.