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 1.32 g/cm³, yet no other measure of soil structure indicates any issue with compaction or poor structure. The saturated hydraulic conductivity is high at 920 mm/hr is extremely high, and the topsoil has over 10 % drainable porosity which should ensure good drainage and aeration. This indicates the A11 horizon has a good level of well connected and functional macropores. The A11 horizon contains 28.7 % or 48.9 mm plant available water (PAWC) which is large, of which 12.6 % or 21.5 mm is readily available for tree growth. Although even more dense than the A11 horizon at 1.62 g/cm³, the A12 horizon also has excellent moisture retention properties. Together the A11 and A12 horizons contain 35.8 mm of readily available soil water and a PAWC of 81.2 mm to a depth of 30 cm, which is considerably greater than most other soils in this study.

The A2 horizon is extremely compact having a bulk density of 1.85 g/cm³. Yet somehow it has higher drainable porosity at 9.2 % than the two A1 horizons. The A2 horizon also contains a moderate amount of readily available soil water at 6.4 % or 12.9 mm. The B21 horizon has only 4.0 % readily available soil moisture, in which most soil water is held too tightly to be accessed by trees.