Decay development of trees bole following logging damages in a 10 years period in mixed beech forest (Case study of Asalem-Nav forest in Guilan)

One of problems in managing of uneven-age forests is logging damages to residual trees and reducing stand quality and quantity in years after logging operation. In this research, trend of bole decay and economic loses by it, following logging damages, were analyzed at a 10 year period in a mixed beech forest in Guilan province. Volume of decayed section on trees bole was measured by Smalian formula, and volume of standing trees bole was estimated by local tree volume tables via plots of 0.1 ha area and systematic sampling design at the start and end of period. Results showed that volume of decayed bole were increased from 0.48 m3/ha at the start of period to 1.71 m3/ha at the end of period (P