For the rational and sustainable forest use, some representative (reference) areas of ecosystems being high conservation value forests within the leasing estate of Tolshmenskoe, LLC, were selected. After that, the monitoring study for the assessment of the forest breeding, environmental and medium stabilizing functions and the reproduction capacity of the preserved forest ecosystems was carried out. Within the ecosystems, six sample sites were drawn and the survey based on the standard forest ecology methods was performed. The objects of the study (sample sites) were shaped to cover the maximum of all types of forest communities available at the leasing estate. Generally, the monitoring observation showed that the arboreal plants growing in the studied sample sites featured high resistance. The forest formation process is continuous but requires some silvicultural practices, such as appropriate care to stimulate the domination of the economically valuable wood species.