Silvicultural–Dendrochronological Evaluation of Thinning Efficiency of Scots Pine Forests in Arid Conditions, Kazakhstan

Abstract

The data of silvicultural and dendrochronological evaluation of thinning efficiency in Scots pine (Pinus sylvestris L.) forests of arid conditions in Kazakhstan are given in the example of the Kazakh Upland for a 70-year period. Scots pine is one of the main forest species in Kazakhstan. Increasing the sustainability of forest plantations and the possibility of forming recreationally attractive landscapes through thinning is an urgent issue for plantations growing in arid conditions. The aim of this work is to evaluate the effectiveness of different intensities of thinning over a 70-year period by silvicultural and dendrochronological methods in dry Scots pine stands of the Kazakh Upland. As a result, a general regular increase in the annual ring width, according to the control in each subsequent 10-year period after moderate and heavy thinning, was noted. It was proved that the greatest positive effect of increasing the main taxation indicators, including radial growth, is via heavy thinning. Statistically significant difference was found in the indicators under consideration between control and stands that were thinned. In Scots pine stands with a high density of forest growing in dry conditions, so it is recommended to carry out one or two procedures of heavy thinning (26–35% of stock) based on the low selection. The first thinning is recommended to carry out at the age of 25–30 years, the second 40–50 years, with the canopy cover of the stands decreasing to 0.7–0.8. In the subsequent period after thinning, it is recommended “if necessary” to carry out sanitary felling in combination with weed control. © 2025 Istanbul University-Cerrahpasa. All rights reserved.