EN
The aim of this study was to specify the above-ground biomass structure of black alder as well as to assess the influence of habitat conditions on biomass size and on allometric relation between biomass and breast height diameter. The empirical material consisted of 67 sample trees in age from 6 to 20 years selected from 17 stands growing on two types of forest habitat. The average share of stem wood in aboveground biomass of trees was 61.04%, branches 18.89%, bark and leaves 11.31% and 8.76% respectively. The fact that the examined stands constituted habitat type did not substantially influence either the biomass size or the relation between biomass and breast height diameter.