A study was conducted of the influence of the rate of application of simulated acid rain on N mineralization and nitrification in a forest soil. The rates were varied by applying different quantities of simulated rain for varying periods of time. The soil was exposed in the laboratory to simulated rain at pH 3.5, 4.1,, or 5.6 at rates equivalent to 1.5, 2.3, 4.6, 7.1 or 15 times the average rate of precipitation in the field and then mineralization of soil N or oxidation of added ammonium was determined. The rates of N mineralization were inhibited by precipitation at pH 3.5 or 4.1 when applied for 27-234 days at rates 1.5 times greater than that which occurs in nature. N mineralization was not affected by simulated rain at pH 3.5 or 4.1 in soils exposed for 156 days at 2.3 times the natural rate of precipitation, for 27 or 81 days at 4.6 times the natural rate, for 54 days at 7.1 times the natural rate, or for 234 day at 15 times the natural rate. (Copyright (c) 1986 by D. Reidel Publishing Company).