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The objective of this paper was to determine the optimum ignition temperature to measure precisely the total and organic P contents of animal manure composts by the dry combustion method. Total P content of the composts was measured by the wet digestion method and the dry combustion method, while the organic P content was measured by the fractionation method and the dry combustion method. Total P content of the composts ranged from 4.43 to 48.6 g kg−1 and there were significant correlations between the total P content measured by the wet digestion method and that measured by the dry combustion method at 550°C. Organic P content measured by the fractionation method ranged from 0.44 to 8.62 g kg−1. Organic P content measured by the dry combustion method ranged from 0.10 to 8.63 g kg−1, and there were significant correlations (r = 0.951) between the data obtained by the fractionation method and those obtained by the dry combustion method at 550°C. Ignition at 240 and 350°C was insufficient to comple...