Особливості росту і продуктивність соснових насаджень із піднаметовими культурами дуба червоного

Abstract

The priority task of forestry science and forest-cultural practice is to study the influence of introduced species of woody plants on growth, productivity and quality of pine stands. Therefore, the purpose of this scientific research was to identify the features of growth and productivity dynamics of pine stands with artificial red oak admixture, created in the last century at the Boyarka Forest Research Station. All 16 sample plots were established in the fresh pine sites. Stands are mostly pure in composi tion, the proportion of red oak does not exceed 20 %. Pine stands are represented by different age groups: young, mid-aged, maturing and mature. The biometric indices of pine stands with artificial red oak admixture, features of their growth and productivity dynamics have been determined. The understory is represented by red oak, which in some cases reaches the height of the main canopy. Highly productive pine stands are characterized by Ia, Ib site index classes. As a result of the modeling of the dynamics of mean heights, diameters, and basal area, it was established that height growth of pine stands is described by the power equation with a high value of determination coefficient: R2 = 0.914. Analysis of the dynamics of height growth of the pine stands with red oak understory demonstrates the difference from the growth patterns of pure pine stands. The high thinning intensity of the researched stands at young age leads to a decrease of their height growth, as compared with other pine stands. At the age of 60 years, the heights become equal, and at the maturity age, stands with understory canopy dominate by height growth over pure pine stands by 4.4 %. At the age of maturity, the difference in the diameters between pine stands with understory canopy and pure pine stands of Ia site index class reaches 6.7 %. Peculiarities of growth of pine stands with understory canopy impose their imprint on the actual productivity of pine stands. The productivity of pine stands with red oak understory, starting at the mid-aged group, steadily rises and at the maturity age reaches the Ib site index class. This proves the viability of introduction of red oak under the canopy of pine stands.