ABSTRACT
Site-specic crop management (or site-specic management, SSM) is a means of managing the spatial variability of edaphic (i.e., soil related), anthropogenic, topographic, biological, and meteorological factors inuencing crop yield. The aim of SSM is to increase crop productivity, sustain the soil-plant environment, optimize inputs, increase protability, and minimize detrimental environmental impacts. The spatial variability of edaphic factors is a consequence of pedogenic and anthropogenic activities, which produce variation in soil physical and chemical properties within agricultural elds. In the arid southwestern United States, the primary soil properties inuencing crop yield are salinity, soil texture and structure, plant-available water, trace elements (particularly B), and ion toxicity from Na+ and Cl− (Tanji, 1996).
