Evaluation of steam distillation procedures for the routine determination of inorganic soil nitrogen

In order to select a reliable routine analytical procedure for the extraction and estimation of inorganic N in South African soils three steam distillation procedures were compared. With the one procedure the soil sample is shaken with 2,0 ? KCl for one hour and the extract is then analyzed by distillation. With the other two procedures the soil sample is distilled directly with either 2,0 ? KCl or distilled H20, eliminating the extraction step. The three procedures yield results for NH4 +‐N and N03 ‐‐N which can be regarded as identical for all practical purposes. It may be recommended with confidence that one of the direct distillation procedures be employed for routine soil analyses.