A field experiment was designed to evaluate the effects of differing forms of acidifying S and N compounds on the chemistry of soils and soil solutions in a low elevation coniferous forest in northern New England. Treatments consisted of O, 1500, 3000, and 6000 eq of SO₄ ^2– or NO₃ ^– ha^–1 for the 1987 growing season applied biweekly as H₂SO₄ or HNO₃, or in a single application as dry] (NH₄)₂SO₄. Acidifying treatments resulted in a significant increase in soil solution SO₄ ^2– (1.2 to 2.6) or NO₃ ^– (12 to 80) in the upper B horizon. Excess strong acid anion leaching was associated with an accelerated loss of base cations, particularly MG²⁺ As solutions passed through the upper 25 cm of the soil profile, mean SO₄ ^2– concentrations decreased by 5 to 50% of the initial values, indicating that much of the applied SO₄ ^2– was immobilized in the upper portion of the pedon. Elevated concentrations of adsorbed and water-soluble SO₄ ^2– indicate that abiotic adsorption of SO₄ ^2– by soils is the dominant mechanism for the initial attenuation of SO₄ ^2– concentrations in these solutions. Other soil properties showed only small or no change due to treatments over the single growing season of this study. These results indicate that H₂SO₄, HNO₃, and (NH₄)₂SO₄ can all effectively increase strong acid anion concentrations in the soil-soil solution system.