The objective of the present study was to evaluate the composition of B horizon equilibrium soil solutions from selected Maine forest soils. The B horizon was chosen for evaluation because it (1) best expressed the weathering processes active in the soil, (2) occupied the greatest volume of the solum, (3) had the most complex chemistry of the major horizons, and (4) provided the major corridor in forested ecosystems for subsurface flow and chemical alteration of ground waters.