SILVICULTURAL AND BIOLOGICAL PARTICULARITIES OF KOREAN PINE WHEN INTRODUCING IT IN THE CENTRAL BLACK-EARTH REGION OF RUSSIA

Abstract

Introduction Prohibition of wood harvesting in the Far-Eastern cedar-broad-leaved forests (1990) resulted from the serious decline of this formation and no effective measures in the sustainable forestry management. The variety of raw and environment-forming functions of cedar forests ensures the  increased attention for the forests, requires the conservation of their populations and cultivation of cedar in plantations beyond the natural habitat. The goal of the research is to ground a long experience of growing the Korean pine with other introduced species in conditions of Central Black-Earth region (Russia). Objects and methods of research. The objects of the research were located in the territory of the former Semilukskiy tree nursery in Voronezh oblast and   forest-park of Russian Research Institute of Forest Genetics, Selection, and Biotechnology. The biogroups of Korean pine (Pinus сoraiensis) of 42-year-old, growing together with White fir (Ábies cóncolor), Sakhalin fir (Ábies sachalinensis), Balkan pine (Pinus peuce), European spruce (Pícea ábies), Siberian cedar (Pinus sibirica) were studied. The silvicultural-taxational and silvicultural-ecological research methods were used. Results. Research has shown that the introduced Korean pine surpassed the Siberian cedar on indicators of its growth and development: in height at 60 %, stem diameter –  at 40 %, crown radius – 34 %, crown length – 56 %. Besides, it has better cleanability from branches (59 %).  Thus, the opinion of less perspectiveness  of Korean pine in comparison with Siberian cedar can be refuted. Korean pines of the tree nursery are as high as the trees of natural stands of II bonitet of Primorski Krai, their diameter is similar to the diameter of trees of natural stands of II bonitet of north-eastern regions of China. The increment in height varies from 0.03 m (initial stage) to 0.61 m throughout the life, and the peak of increment is within the period of 22-32-years old. There has been observed a successful interinfluence between the Korean pine and White fir and Sakhalin fir. The yield of one own-root tree of Korean pine (40-year-old) was 20 cones (cone length was 91 – 118 mm; width – 63–79 mm), there were from 16 to 45 seeds in a cone. The seed fullness was from 38.5 to 89.3 % with a mean of 67.4 %. Mass of 1000 seeds was from 374 to 802 g. (mean mass - 568 g). Conclusion. Korean pine is better than the Siberian cedar in terms of grown and development when introducing in the Central Black-Earth region of Russia. Thus, this species is a perspective one. Korean pine is of considerable variability both between the clones of the studied objects and relating to the climate conditions that makes it possible to select the perspective genotypes in order to establish the introduced populations.