The distribution of soil P among inorganic and organic forms was examined in prairie and boreal forest soil profiles from Saskatchewan, Canada. A sequential extraction procedure was employed to separate P into labile and stable inorganic (Pi) and organic (Po) fractions. Profile depth, climate, vegetation, and cultivation all had a major influence on the distribution of P which is attributed to differing intensities of pedogenic processes such as weathering and leaching, and their relationship to P transformations in the soil environment.