Changes of assortment structure of Scots pine stands of Ist site index class in Pisz Forest District

In spite of the growing importance of the protective and social functions of forests, their productive function, including production of raw wood with a diversified assortment structure, is still prominent. Changes in the assortment structure depend to a large extent on tree species, habitat conditions and intensity of tending treatments. However, for the temporal organization of forest management, it is essential to recognize the dynamics of these changes in relation to stand age. The paper contains an analysis of quantitative and qualitative changes in the assortment structure of the Ist site index pine stands in the Wilcze Bagno Forest Compartment (Pisa Forest District), depending on the length of the primary production of standing timber. Data from 10 forest stands similar in terms of habitat, stand density and management treatments were taken for analysis. These stands form a homologous series ranging in age between 40 and 130 years.