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Field studies showed that the use of phosphate fertilizers increased the amount of water present in the soil and facilitated tillage. Crop yields were closely related to the increased water content. Laboratory studies showed that P appreciably increased the water‐holding properties of soils. This was found to be directly related to the increase in the negative charge of the soil particles and the charge was closely related to the Al‐phosphate/Fe‐phosphate ratio. In general increases in water‐holding capacity were caused only by the larger rates of P, but in some instances 50 ppm P gave significant increases.