A method for separating the hydrolysis products of monocalcium phosphate to test their effects on soils and crops

A method was developed to test separately on crops the compounds formed when a granule of concentrated superphosphate hydrolyses in soil. An amount of monocalcium phosphate (MCP) equal to that in a granule of superphosphate was placed in a small glass tube with glass fibre filter paper on its base; a moist plug was put in the top of the tube which was placed on moist soil in a pot; the whole was covered and left for six days. MCP hydrolysed and triple-point solution moved into the soil. The residue in the glass tube was transferred to another pot. In laboratory experiments the composition of the residue was that of dicalcium phosphate showing that the products of hydrolysis were like those from MCP hydrolysed in concentrated solution. Movement of the triple-point solution in soil was similar to that in experiments made by Tennessee Valley Authority.