Contribution to the research of the bark properties of several wood species

The paper presents the results of the research into the density and hardness of the bark of beech, hornbeam, oak, ash, poplar and fir. These bark properties were examined on samples taken along the length of the log from the ground to the 7 cm diameter. The results show that density of the bark is 6 to 14% greater than the density of wood of particular species. The hardness of bark is 2.3 to 6.6 times lower than the hardness of wood, but the values are not uniform, differentiating the hardness of the integral bark, the hardness of phloem (inner bark) and of rytidoma (outer bark).