Thirty-eight soils from forest sites in central Germany dominated by beech trees (Fagus sylvaticaL.) were sampled to a depth of about 10 cm after careful removal of the overlying organic layers. Microbial biomass P was estimated by the fumigation — extraction method, measuring the increase in NaHCO3-extractable phosphate. The size of the microbial P pool varied between 17.7 and 174.3 μg P g-1soil and was on average more than seven times larger than NaHCO3-extractable phosphate. Microbial P was positively correlated with soil organic C and total P, reflecting the importance of soil organic matter as a P source. The mean microbial P concentration was 13.1 of total P, varying in most soils between 6 and 18. Microbial P and microbial C were significantly correlated with each other and had a mean ratio of 14.3. A wide (5.1–26.3) microbial C: P ratio indicates that there is no simple relatinship between these two parameters. The microbial C: P ratio showed strong and positive correlations with soil pH and cation exchange capa
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