Abstract: Relative changes in organic matter in soil in an agricultural field are mapped by a computer-implemented system and method that uses a number of individual bands from one or more remotely sensed images of the agricultural field. Each of the bands is associated with a light spectrum wavelength range, and each of the bands is weighted based on its contribution to predicting relative changes in organic matter. Elevation data may also be used in the weighted calculation. The map is separated into zones based on the relative predicted organic matter falling within a predefined range. Each zone may be associated with a different average organic matter content, and nutrient supplements are recommended for each zone based on the average organic matter associated with each of the mapped zones.