A ROBUST METHOD FOR ESTIMATING SOIL PROPERTIES IN UNSAMPLED CELLS

For site-specific crop management (SSCM), fields are viewed as collect ions of small regions (cells) in which soil properties are nearly unif orm. A field information system (FIS) can be used to store soil fertil ity data and to create application rate maps on a cell-by-cell basis. A data blocking procedure was developed to convert soil sample data in to a new data set in which one value represents the soil property in e ach cell. A nonparametric distance-weighting algorithm was developed w hich produced about the same estimation errors as a kriging method, bu t was much faster. Example applications of the data blocking procedure to KCl extractable nitrate and soil organic matter data are included.