A scheme involving aspects of both the Bowman and Cole [54] and the Hedley et al. [56] procedures was developed for analysis of organic phosphorus in wetland soils [35]. This involved initial extraction of labile compounds in 0.5 M NaHCO3 at pH 8.5, fumigation to estimate microbial phosphorus, an acid extraction in 1.0 M HCl, and finally extraction of stable organic phosphorus in 0.5 M NaOH. Organic phosphorus extracted in hydrochloric acid was included in the moderately labile pool. Residual phosphorus was determined by ignition and acid extraction.