The article presents the results of studies of radial growth variability and dynamics of in a number of old-growth oak and elm trees, growing in Moscow and recognized as natural monuments within the framework of the Federal target Program "Trees monuments of wildlife". The following tasks were solved: the formation of a sample trees from the database; the construction of tree-ring chronologies based on wood cores in the collection of botanical samples of the database; study of the variability patterns of the annual rings and comparative analysis of chronologies for different accounting trees. As a result, it is shown that promising directions of research work with old trees is the construction of long-term chronologies for them, the analysis of dendrochronological information and propose of measures for their care on the basis of monitoring data. The expansion of the dendrochronological information using in the field of woody plants monitoring and tree care in an urban environment is an urgent topic for research. Identification of local years of maximum and minimum growth is important for further identification of factors that favorably and adversely affect plant growth. At this stage of research, it is established that the temperature regime at the beginning of the growing season is significant for the good and bad growth of the studied accounting trees as a whole. The positive effect on the growth of elevated temperatures in May is particularly clear.