Precision farming revolves around the use of information-based technologies. The prescriptive nature of precision farming requires immense data to be effective. From the biological standpoint, most of this information is currently obtained from plant mappings and scouting reports. These means of information gathering are time consuming and expensive. Crop simulation models and plant mappings can provide most of these vital biological data. The first year results of adapting the ICEMM-cotton simulation model to a precision farming study at the King Ranch in Kingsville, TX, show promising use of the model. A 100-acre field divided into 20 blocks was used for the study. Agronomic practices, daily weather data and soil physical and chemical properties (collected at the start of the planting season) were used as inputs to the model. The dates of occurrences of developmental events were predicted within 2 days of actual occurrences. The final plant height and node numbers were close to the observed values in the 20 blocks. Although the overall average yield data approximated the actual yield, individual block yield comparisons were inconsistent, partly due to erroneous soil hydrologic parameters.