Adjustment period and constrained maximum clearcutting volume in the new Collective Forest Management Plan System in Japan

Abstract

In the new Collective Forest Management Plan System in Japan, introduced in 2012, a formula similar to the Austrian formula is used to define the maximum clearcutting volume,andthe standard cutting cycle is considered anadjustment period. However,if the current stand volume exceeds the assumed normal growing stock, the allowable clearcutting volume is less than the expected harvest volume that decreases the stand volume to the standard volume within the adjustment period. This is because the end of the adjustment period is deferred in the calculation of the allowable clearcutting volume after the first planning period. This rule constrains the maximum clearcutting volume after the first planning period. The constraint is relatively severe in clearcutting of broadleaved stands where the standard cutting cycle is short(short adjustment period) and the relative current stand volume is higher than the normal growing stock.