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A combined spatial-aspatial clustering approach for partitioning tree-based data in orchards was developed. The method employs the Getis-Ord Gi* statistic applied to the analysis of individual tree data in a grapefruit orchard located near the city of Adana, Turkey. Analyzed tree-variables included yield (total fruit weight per tree) and two possible yield-determining variables, tree size measured as tree trunk circumference (cm) and soil properties measured by the soil apparent electrical conductivity (ECa (mS/m)). Data were collected from 179 trees. The developed method was applied to the analysis of ‘hot-spots’ (clusters of high data values) and ‘cold-spots’ (clusters of low data values) in orchards and compared to the k-means clustering algorithm, an aspatial clustering method widely-used in agriculture. The combined method improved results by both discriminating among feature values as well as representing their spatial structure and therefore represents a superior technique for identifying homogenous spatial clusters in orchards. The approach can be used for delineating management zones for optimal precision management of tree crops.