FIG. 1. Instrument temperature effect, defined here as the apparent change in soil water content () due to Hydra Probe electrical components when subjected to a 40°C temperature change, plotted as a function of the actual water content. For example, if soil at 0.30 m³ m^–3 experiences a temperature change of 5 to 45°C, the instrument effect will cause an apparent water content rise of about 0.007 to 0.307 m³ m^–3.