The system of decision support to optimize the mode parameters of accelerated growth of planted forests in the form of the structure of information flows between the object and the control system is considered. Solution of control problems is possible only if there is a certain amount of knowledge or information about the quality and quantity of internal connections be-tween the elements of the controlled object and external communication components and the entire object with the environment. A mathematical model of the dynamics of even-aged coniferous plantations is presented and the objective function of process control for fasted growing of conifer plantations is highlighted.

Creating forest plantations, used in these soil preparation techniques, agricultural activities, as well as the selection of the optimum species composition and subsequent silvicultural treatments are developed in accordance with different types of forest conditions. These conditions greatly affect the overall performance and progress of growth stands. The results of numerical analysis and the use of tables of plantation growth of Scots pine growing in various types of forest conditions (A2, B2) are given, reflecting changes in the stock of stem wood with age under the influence of thinning. According to the cutting age (maturity) for Scots pine optimal thinning regimes are presented in protected forests of forest-steppe region of the European part of the Russian Federation. To determine the optimal regimes of thinning of forests computer program was used that allows you to optimize conducting of thinning and calculate the objective function of stem wood for different target diameters of technical maturity. Computer calculations made it possible to compare the effectiveness of silvicultural thinning in Scots pine plantations according to standard regulations and recommended modes of forest care. Proposed options of thinning are different in conducting more intensive thinning at the age of clearings at forming the composition of plants and relatively low percentage of thinning at the age of caring for growth stands. The comparative characteristic of the performance of Scots pine plantations and the target output function of stem wood depending on the desired diameter is given. As a result of numerical calculations some conclusions and recommendations for thinning in pine plantations were obtained, depending on the type of site conditions.