The article is devoted to testing the hypothesis about the current increase in the forest cover of raised bogs in the forest zone, depending on changes in climatic conditions. To analyze the dynamics of forest cover using the example of raised bogs in the Tver region, a methodology was developed based on the use of different generations of Landsat satellite data. The methodology was tested on ground data and applied to analyze changes in forest cover between 1976 and 2022 in several raised bog areas, including undisturbed areas and areas drained for forestry. The study tested approximately 20 vegetation indices across a variety of surveys, including summer and winter (snow) conditions. The classification results were verified using planting taxation data on circular plots and assessed using error matrices. Moderate-resolution Landsat satellite imagery, especially winter imagery, has been found to be suitable for long-term analysis of afforestation dynamics in raised bogs. An optimal vegetation index SWVI (Short wave vegetation index) and classification technique are proposed. The results of the study showed that afforestation increases in all undrained areas of swamps, regardless of their initial state. The smallest changes are observed for areas with low crown density (0-0.1), to a greater extent for density 0.2-0.3, and the greatest changes occur in areas with high crown density (0.6-0.7 and higher).