The distribution of organic matter and mineral nutrients in a 34 yr old stand of red alder (Alnus rubra) in Washington State, USA, is described, together with the annual nutrient transfers between components. The nutrients studied were N, P, K, Ca, Mg and Mn. There was a large quantity of N in the ecosystem, presumably because of N-fixation by the alder. The stand was deteriorating and thus there was a high quantity of wood in the litterfall. The understory made an important contribution to the biomass, stand productivity and return of mineral nutrients to the forest floor. Comparison with a nearby stand of Douglas-fir (Pseudotsuga menziesii) of similar age indicates that, while the organic matter distribution is similar, they have different patterns of nutrient accumulation and cycling. Data from an over-mature 450 yr old Douglas-fir stand are also included so that a comparison of 2 deteriorating stands can be made.