The results of the cultivation of Scots pine (Pinus sylvestris L.) in the provenance trial in the Serebryanoborsky experimental forest district of the Institute of Forestry of the Russian Academy of Sciences are summarized. The silvicultural effect was assessed by a comprehensive indicator of the feasibility of introducing specific pine conventions. It was established that the use of pine seeds of exclusively local provenances cannot be considered justified. In the vast area of pine there are very remote populations of a local nature, the seed of which, when moved, can be successfully used to create highly productive artificial stands. The 68 year old geographical plantations of larch growth and production rates of 18 climotypes of 14 larch species were compared. These species are Polish larch (Larix polonica Racib.), European larch (Larix decidua Mill. f. Sudetica), Larix sukaczewii Dylis, Siberian larch (Larix sibirika Ledeb.), Larix cajanderi Mayr., Larix gmelinii Rupr., Larix Czekanovskii Szaf, Larix amurensis Kolesn., Olgan larch (Larix olgensis Henry), Japanese larch (Larix kaempferi (Lamb.) Carrière), Larix kurilensis Maur., Larix principis Rupprechtii Maur., Larix potaninii Bat, American larch (Larix laricina (Duroi) K. Koch). Polish larch, Japanese larch, European larch and Olgan larch have the best growth rate results. Climotypes from Siberia and American larch showed worst results. Polish larch (812 m3/ha) and Japanese (804 m3/ha) larch from the Southern Sakhalin have the highest stem volume. The final estimations showed that the climotypes of Polish larch, European larch from Sudetes and Japanese larch from the Southern Sakhalin are suitable for introduction in the Moscow Region. The climotypes from the Far East, namely Larix amurensis Kolesn., Olgan larch and Larix kurilensis Maur., had positive silvicultural effect. The inland climotypes from Asia together with American larch showed negative results.

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The results of studies of the under-canopy population of spruce (Picea abies L.) in over-mature birch forests (Betuletum oxalidosum) of the Moscow region are presented. The purpose of the research was to study of the renewal process periodicity, age, vertical structure and condition of the spruce population. The work was carried out on a permanent trial plot in the period 2008–2018. The undulating feature of the spruce renewal process under the canopy of birch forest with a frequency of 30–40 years within the age of the birch trees under consideration has been established. It is determined that the basis of spruce forests formed under the canopy are trees with a renewal period of less than 30 years, which by the onset of the decay of birch forests form the first and second layers with an average age approaching the age of quantitative maturity. The age structure of the spruce population in birch forests aged 115 years is characterized by the dominance of trees of two age groups — 21–40 and 91–120 years, which account for 29 % and 37 % of the population, respectively. The emerging spruce forests belong to conditionally even-aged stands. Trees with a height of 2,0 m dominate (about 40 %) in the vertical structure of the population. The age dynamics of the stand is aimed at a slight increase in undergrowth trees and the first storey, and a decrease in the number of the second storey trees occurs. This is due to the emergence of new spruce specimens and the transition of part of the trees of the second storey to the first one. It was found that weakened trees predominate in the under-canopy population of spruce in overmature birch forests. Trees of the first layer are in the best condition (status category CS = 1). The state of undergrowth trees during the observation period did not change, remaining weakened (CS = 2,3–2,4). The set of trees of the second layer was characterized by positive dynamics — from the category of strongly weakened (CS = 2,7), due to the mortality, it moved to the category of weakened (CS = 2,0). Trees with a renewal period of up to 30 years are in the best condition. As a result of the succession process, after the decay of birch forests, low-density spruce forests with a productivity corresponding to the III site class will be formed.

In the district part of «Losynyi Ostrov» National Park the state of plantations bound for clear sanitary felling based on the results of an earlier forest pathological survey was studied. 58 plots with a total area of 98,8 hectares, located in the specially protected and recreational zones of the national park, were examined. «Losynyi Ostrov», which has a relatively small area, is located at the junction of the three forest-growing regions; on its territory there is a unique wetland complex of the Yauza river and its tributaries. This led to a wide variety of natural conditions. At the same time, the national park is surrounded by densely populated urbanized areas. Recommendations to create forest plantations in areas with decayed stands were made, being based on the analysis of the historical experience of creating artificial plantations in «Losynyi Ostrov», edaphic and hydrological conditions, as well as considering the designated purpose of forests within each functional zone. 8 variants of forest cultures are proposed for each functional zone. The main and alternative crop options at each site are considered. The substantiation of the species range and the stand composition of pure and mixed crops, which are determined taking into account the designated purpose of forests, the potential of the forest growing conditions of the site, the type of forest, the type of soils and their moisture content, are given. Taking into account the designated purpose of forests, perennial tree species that are resistant to adverse environmental factors and are capable of forming in the future highly productive, recreationally attractive and long-lived plantations, corresponding to the historically formed natural environment of the national park, are preferable. Pine, spruce, linden, oak and larch are suggested as the main species, accompanied with elm and ash. It is concluded that the density of planting crops of more than 2 thousand pieces/ha in the recreational zone is impractical, since such plantings will be more comfortable for recreation. In a specially protected area, the appropriate planting density is 3–4 thousand pieces/ha.