Abstract
A relation between drainage and soil water content was obtained under conditions of no evapotranspiration. It was assumed that for a given cropped soil, drainage rate was a function of water content and independent of evapotranspiration rate. With evapotranspiration rates known, drainage could be calculated. Good agreement between measured and calculated soil water depletion was obtained with three soils ranging in texture from sand to silt loam and at evapotranspiration rates of 0.4 to 1.3 cm per day. A relation between drainage and soil water content was obtained under conditions of no evapotranspiration. It was assumed that for a given cropped soil, drainage rate was a function of water content and independent of evapotranspiration rate. With evapotranspiration rates known, drainage could be calculated. Good agreement between measured and calculated soil water depletion was obtained with three soils ranging in texture from sand to silt loam and at evapotranspiration rates of 0.4 to 1.3 cm per day. © Williams & Wilkins 1974. All Rights Reserved.