FIG. 1. Water retention (), hydraulic conductivity (K), water capacity (C), and water diffusivity (D) for loam (continuous line), clay loam (dashed line), and clay soils (dotted line) as a function of pF = log₁₀(|h|), where h is the water potential (cm). Root conductivity is given by the gray horizontal line. Open circles characterize the threshold at which the soils and the root have the same hydraulic conductivity.