SIBERIAN STONE PINE IN THE FORESTS OF MIDDLE VOLGA REGION

Abstract

Introduction. A Siberian stone pine (Pinus sibirica Du Tour) is one of the most durable and valuable tree species, which naturally grows on a variety of sites and gained a reputation of environmentally flexible species. In the Middle Volga Region there are no natural Siberian stone pine stands, however there is a large number of plantations. The relevance of the work is in improving the environmental-resource capacity of the region by proper introduction and growing of invasive species. The work is aimed at the evaluation of the contemporary condition of plantations including Siberian stone pines in the Middle Volga Region and detecting regularities in their development. Materials and methods.  For the purpose of current research we referred to the e-data base of the Forest Fund, containing detailed inventory characteristics of Siberian stone pine growing in different forest site types of the Mari El Republic, the Chuvash Republic, the Republic of Tatarstan and the Kirovskaya Region. The total area covered with Siberian stone pine reached 780.0 ha, from 281 forest plots. The research method included a systems analysis of mass inventory data obtained from plantations using the algorithms, developed by Prof. Yu.P. Demakov. Results. Siberian stone pine plantations found in Middle Volga Region  are mainly  represented  by  young forest of  1-2 age class growing in almost  any forest site type. The Siberian stone pine is mostly widely spread in fresh suramens (53.4 %) and oak forest (15.6 %). The average presence of Siberian stone pine in forest stands is 36.3% varying from 1 to 10 units. The pure complete species represent 8.1%.  Siberian stone pine is most productive in fresh suramens and oak stands with 1.9 quality class. The native forest plants inhibit the growth of Siberian stone pine. The growth rate of the species under study is most closely correlated with that of spruce, particularly what concerns forest site type C₂. Conclusions. On condition of proper approach to growing Siberian stone pine species and sufficient foresters’ attention to the growth process in the Middle Volga Region it is possible to gain high timber yield, as well as other valuable products this species can offer: nuts, resin, needles.