The structure of tree stand and wood-destroying fungi of native pine biogeocoenoses of the Russian plain

The author considered age structures of virgin indigenous pine forests of natural origin as well as plantations in the subzones of taiga, zones of mixed forests, deciduous forests and forest-steppe of the Russian plain. Native pine forests are heterogeneous by their structural characteristics. This heterogeneity is caused by high demands of the species to understory light requirements as well as by frequent pyrogenic influence that determine the age structure of stand forests. Virgin pine forests have up to 14 age generations and from 5 to 20 % of stand trees affected by fungi of biotrophic complex. That has a direct connection with their dynamic status. In the pine forests of digressive dynamic faze, where the initial age generations accommodate the major biomass amount, this volume may grow up to 50 %. Pine species planted discounting regularities of formation of stable forest communities are subject to spotty attacks by fungi of biotrophic complex. A species composition of wood-destroying fungi of biotrophic complex causing rot defects of pines in the entire longitudinal gradient of pine distribution within the Russian Plain stays virtually unchanged. Significant changes can be noted only in the occurrence of certain types of wood destroying fungi. The main types of wood biotrophic fungi include: Climacocystis borealis (Fr.) Kotl. et Pouzar, Heterobasidion annosum (Fr.) Bref., Phaeolus schweinitzii (Fr.) Pat.; Porodaedalea chrysoloma (Fr.) Fiasson et Niemelä; Phellinus pini (Thore: Fr.) A. Ames [= Porodaedalea pini (Brot.: Fr.) Murrill]. In the uneven-aged pine forests of natural origin, mottled butt rot does not form drying out spots and exists in the stands as an ordinary component of the total biotrophic defeat. Wood-destroying fungi of biotrophic complex are evolutionary determined as one of the endogenic mechanisms of destruction of unstable forest structures and formation of stable ones. The author also evaluated the volumes of biotrophic complex’ wood-destroying fungal attack and described the features of mottled but rot (Heterobasidion annosum (Fr.) Bref.) affection in the pine forests