A study was made of the changes and variation in the chemistry of rainwater passing through the different strata of separate ecosystems of four tree species (oak, alder, spruce and pine) on the same site at Gisburn (Bowland Forest), north-west England. Waters were sampled as rain, throughfall, forest-floor leachate and soil waters from both the A and B/C horizons; and analysed for NH 4 -N, NO 3 -N, PO 4 -P, K, Ca, Mg, Na, Al, SO 4 -S, Cl, total organic carbon and pH. Species differences — often marked ones — appear to exist in the concentrations of most solutes in most strata. The between-species differences in throughfall chemistry provide little guide to the chemistry of waters lower down the profile: the forest floor is a particularly important source of further species differences, e.g. variation in NO 3 production and the resulting effects on acidity and other ions. The chemistry of the soil waters provides some indication of possible drainage losses, although the question of which horizon acts as the source of drainage waters on this site remains unanswered. The levels of H and Al, in particular, are very different between the upper mineral soil (A horizon) and the lower B/C horizon. In general, and based on these concentration data only, oak is associated with smallest potential solute losses, pine the greatest.