Regression equations for fractions of forest phytomass have been developed for European Russia (including the Urals). These equations are based on available data and findings given in publications (962 sample plots have been examined). The analyses cover pine, spruce, oak, birch, beech, aspen, alder, and lime species. Together these eight species constitute some 95% of the tree cover of the forested areas in European Russia. The equations allow us to evaluate the ratio between the weight of phytomass fractions and growing stock by species, age classes, and site indices. Application of the phytomass results to the Forest State Account (FSA) data (1988) gives an estimate of a total (living) phytomass in the forest ecosystems of forested areas of European Russia (166 million hectares of forested area, 20.28 billion m(3) of growing stock) of 15.47 petagrams (Pg) of dry matter (which corresponds to a density of 9.32 kg/m(2)). The total carbon pool is estimated to be 7.64 Pg of carbon (C) with an overage density of 4.60 kg C/m(2) in 1988. Sensitivity analyses of data and methods show that the results of the equations probably underestimate the values for phytomass and carbon by about 5%. Total phytomass in the forest vegetation of forested areas based on the 1993 FSA inventory is estimated to be 16.94 Pg (with an average density of 10.36 kg/m(2)) and the total C content is estimated to be 8.37 teragrams (Tg) (with an average density of 5.03 kg/m(2)). Changes in the total forest phytomass of the forested areas during the 1966-1993 period were estimated to be 4.73 Pg (or about 174 Tg of dry matter per year), and the carbon content increased by 2.34 Pg. Thus, between 1966 and 1993 European Russian forests were a net sink for carbon and stored and absorbed an average of about 87 Tg of C annually. (C) 1997 Elsevier Science Ltd.