PHYSICAL PROPERTIES OF SOILS UNDER STANDS OF INTRODUCED TREE SPECIES IN THE ARBORETUM MLYNANY, SLOVAKIA

The knowledge of local soil and environmental conditions is considered the key factor for successful introduction of exotic tree species. Therefore, the objective of this study was to determine which physical soil properties are appropriate or limiting for the life of the examined introduced tree species in the Arboretum Mlynany. Soil properties were studied in six pits dug under: Prunus laurocerasus, Thuja occidentalis malony, Pinus wallichiana, Cryptomeria japonica, Acer saccharinum, Abies concolor. It has been found that texture of soils under the planted tree species was medium heavy and prevailingly silty-loam, loamy and clay-loam, which suits all of them. Apart from northern white-cedar, other examined trees were planted on soil with appropriate properties, and they showed no abiotic damage. On the other hand, the shortage of water in soil during long summer periods of drought caused physiological symptoms on the individuals of northern white-cedars, mainly increased litterfall of twigs from trees, but also their weak growth. Suitable measure for improving hydrophysical properties of soil under northern white-cedar canopy is an extension of irrigation to their habitat.