The Effect of Utilized Trees Diameter on the Residual Stands in Forest (Savadkuh-Mazandaran)

The logging of trees like the other processes of utilization will create lots of damages for the residual stands in forest. The identification of the types, severity (amount) of the incurred damages, and factors bringing them about are of paramount importance. The aim of this study is to survey the effect of the diameter of trees logged in the residual stands in the fifth section of Valila series of the Mills plan of saturated timbers in Shirga. At first, 50 trees (20%) were randomly selected from 250 marked trees from the various diametrical classes based on the marked protocol. Then 50 semicircle sample pieces in an area of 1500 square meters were selected, and the quantitative (diameter equall to breast and height), and qualitative (eradicated, cracking of crown and stem, and stem and bark peeling) characteristics were measured and registered before and after their logging. The results showed that the diameter equal to breast of logged trees, except in their eradication, can directly have significant impacts on the extent of stem and crown cracking, damaging of stems and peeling of trees, and the greatest damage was also due to the logging of trees in the diametric class of 80 cm and above it.