Investigation on biomechanical properties of pinus nigra Using stress wave technique and resistography

Ensuring the quality and stability of trees as the most important components of the plant community has attracted the attention of foresters to identify and measure defects and ensure safety coefficients. Therefore, in the present study, the use of acoustic tomography to calculate the extent of decay, the area of the woody section and the safety factor of black pine was studied. Acoustic tomography was performed using 16 sensors at two heights of 147 and 200 cm above the ground and on 8 tree specimens in the Sopron region of Hungary. The results showed that the stress wave technique was an accurate method for determining safety coefficients and determining the amount of internal decay in the tree and also had the ability to identify compression areas in cross section. Resistography of the studied sections in different geographical directions assisted to locating the woody areas, which was compatible with the information of acoustic tomography. The findings of this study showed that the area of the canopy has a significant role in the safety of the tree and the possibility of tree fall, so that in some trees due to their condition, with doubling the area of the canopy, the torque increased from 80827 to 161655 N.m and the condition of the tree changed from low-risk to high-risk.