Soil Hydrology Overview

This data reflects both the quality of the soil structure, the amount of water available for growth and the ease by which these soils are able to be irrigated. The data indicates how much water is available for vigorous tree and fruit growth, as well as how much water is available for tree maintenance and survival. This data can also be used to better schedule irrigation, and compare irrigation requirements between soils.

The topsoil (A11 horizon) appears to be slightly compact having a bulk density of 1.38 g/cm³, a moderate to low saturated hydraulic conductivity of 65 mm/hr, and a drainable porosity of 7.9 % which is below the ideal level of 10 % for good root function. The A11 horizon contains 31 % or 31 mm plant available water (PAWC), of which 13.3 % or 13.3 mm is readily available to support rapid growth (Green in Figure 3), an additional 17.7 mm soil moisture is available to the tree but at a cost to growth (Orange in Figure 3), whilst 9.2 mm is not available for use by trees (Red in figure 2). The A12 horizon shares similar properties to that of the A1 horizon, however it has relatively less readily available soil moisture at 7.5 %, and less tightly held water at 11.4 %. Despite having exceptionally high density at 1.84 g/cm³ the A2 horizon has good water retention properties containing 19 % or 28.5 mm plant available soil moisture, of which 8.4 % or 12.7 mm is readily available. The majority of moisture held in the B21 horizon (71.8 out of 115.8 mm) is not available for tree use, with only 4.1 % or 10.1 mm being readily available.