“…(1956), Scott et a_l. (1957), Hanway and Scott (1957), Burns and Barber (1961), Grava et al (1961), Jones et al (1961 ) and Bates (1961) Total K in the soils and minerals was determined by the method described by Jackson (1960, pp. 283-284) except for the fact that the temperature of the sand bath was approxi mately 190° Ce Also, 1.0 to 1.5 g. of soil (oven dry basis) was used and no wetting was required because the soil was already moist.…”