Due to increasing consumer demand for almonds its acreage has significantly increased in California over the last ten years to 1,530,000 acres, respectively. However, deep well-drained soils have become scarce and expensive and production of almonds has expanded into areas with more marginal soils. These marginal soils tend to have higher variability in the soil profile depth, texture, structure, available water capacity, slope, and salinity. This translates to greater orchard variability in both canopy growth and yield. Growers are interested in management practices that can turn this variability from a liability into an opportunity by increasing crop production on the lesser quality soils and improve water, energy, fertilizer, and other production efficiencies. The purpose of the study was to evaluate the effect of soil heterogeneity characterized by variability in soil structure and texture on root-zone soil water dynamics in almond orchards using the Electrical Resistivity Tomography (ERT). The ERTwas sucessfully used to map subrface changes in soil water dynamics under different soil types within the orchards. Most active root water uptake was mostly limited to the upper 0.5 m of the soil profile. Monitoring soil water is useful to prevent water deficits and water/nutrients losses by drainage.
