In my thesis focus on the influence of local conditions on trees, in which they had grown, or had been planted. For these reasons, it is important to track the differences between individuals that lived in different places for generations. Beech, as a species with high phenotypic plasticity is able to react by adaptation. These long-term changes can be observed as changes in genes over generations, or as changes of phenotype. My work focuses on comparing beech proveniences, because of their widespread in Europe. Beech, thanks to its plasticity, is able to quickly and effectively adapt to local soil and climate conditions. We compared hydraulic traits of beech individuals growing on two different plots. One is located in Slovakia and the second one is in Germany. These plots had significantly different conditions. My work mainly focuses on defects in hydraulic traits and changes in xylem anatomy. We observed changes in breast height diameter, height, biomass, specific leaf area, area of one leaf, pressure in xylem with 50% loss of hydraulic conductivity (P50), pressure in xylem with 88% loss of hydraulic conductivity (P88), number of vessels, vessels density and average vessel diameter. The aim of my study is to find out if beech (Fagus sylvatica L.) is able to adapt to harmful effects of low temperatures in the same way as is beech able to adapt to heat or drought. Results have shown us important factor of local conditions on these traits and we confirmed the plasticity of beech. Adapting to extreme temperatures was shown as an important factor, despite the high variability at the provenance level.