Density formation along the trunk radius in various wood species based on latitudinal or altitudinal zoning

Wood is a material characterized by anisotropy of structure and variability of properties in the tree trunk. The indicators of wood properties can be predicted by the density value. Wood density formation in a tree trunk is influenced by many factors. The most important are: age changes, the position in the trunk and the impact of the environment. The purpose of this study is to establish the regularity of wood density formation along the trunk radius. Regularity is based on growing conditions and latitude zoning for Scots pine ( Pinus sylvestris L.) and altitude zoning for European chestnut ( Castanea sativa Mill.). The studies have been performed on cores including wood sections from bark to core obtained using coring instrument. Density of each annual layer by measuring buoyancy force of specimens immersed in a liquid was determined. The formation features and periods of the maximum density of pine and chestnut wood along the trunk radius were established based on latitudinal and altitudinal zoning of wood in the temperate continental climate of the European part of Russia.