The data set presents about 40,000 trees which where surveyed during several Russian-German expeditions by North-Eastern Federal University Yakutsk and Alfred-Wegener-Institute Potsdam to the North-East of the Russian Federation between the years 2011 and 2021. The purpose was to gather information on trees and forests in this region, which was then used to understand tree line migration, stand infilling and natural disturbance and succession processes and to initialize and validate a forest model. Trees are located on more than 160 vegetation plots, each of which has a size of several hundred square meters. For every tree, height was estimated, and the species recorded. Some individuals were subject to more detailed inventory, including diameters at base and at breast height, crown diameters, and other information.