The study of dynamic changes in the spatio-temporal series of forest communities in a non-post-pyrogenic space in specific types of habitats over a long range of succession in specially protected natural areas is a topical subject of research in geobotany, forestry, and nature conservation. The aim of the work is to identify the ecological differentiation of natural and artificial communities of different-aged in the pine forest with mossy landscape in “Grodnenskaya Pushcha” reserve (Belarus, Grodno region). The study of 17 forest phytocenoses on a time series from 5 to 112 years was carried out in 2018 using the trial plot method (400 m2). In the course of the research, a complete accounting of the species composition of phytocenoses was carried out, 86 species of vascular plants, 22 species of epigeic mosses and 6 lichens were identified. Different-aged communities of pine forest with mosses of natural and artificial origin in terms of the spectrum of coenotic groups beco-me similar in the stands aged 40 to 60 years, while a typical forest living ground cover is formed earlier in natural communities (pole stand) than in pine cultures (stands aged 40 to 60 years). In the formed natural and artificial phytocenoses, the ratio of the proportion of the dominant species of the forest coenotic group changes: in mature forest cultures, the projective cover of Hylocomium splendens (Hedw.) Bruch et al. 72,80% more than in natural communities, and Pleurozium schreberi (Brid.) Mitt. less by 49,09%. Three main environmental factors were identified that determine the formation of the studied phytocenoses: forestry activities, lighting regime, and soil trophicity. The ecological interpretation of the factors of the studied communities of the mossy pine forest remained unchanged with a 3-fold increase in the sample.