Effects of the control method (Goc variety) in selection forest management in western Serbia

Abstract

The control method, one of the most reliable methods of selection forest management, has been applied in selection forests of western Serbia in a somewhat modified form (God variety) for fifty years. This paper analyzes the effects of the control method, i.e. its Go variety, in the period from 1960/70 - 2000. It is based on the data of five successive complete inventories of the Forest Management Unit (FMU) "Tara", whose high selection forest of spruce, fir and beech (Piceo-Abieti-Fagettum subass. typicum) trees on diluvium, brown and illimerised soil on limestone, and on limestone in formation with hornfels, are the best quality and the most spacious forests in the Management Class MC 491/1. The effects were monitored through the changes in the distribution of the number of trees and volume per diameter classes, separately for fir as the protagonist of the selection structure, and collectively at the level of a compartment, a typical representative of MC 491/1. Also, the analysis included the changes in the number of trees, volume, current volume increment, yield, and number of recruited trees per unit area (1 ha) by tree species in MC 491/1, occupying an area of 2,648.78 ha. The study results show that in the study period the average volume in MC 491/1 increased by 18.8%, the percentage of conifers increased from 66.0% to 78.5%, and the bearer of the changes was fir. The volume of the mean fir tree increased by 35.9% and it attained 1.086 m(3). The volume increment increased by 15.7%. The selection structure of conifers was satisfactory, but there were problems with beech regeneration, in its stable presence and in its achievement of the targeted structure. The number of trees per unit area (1 ha) decreased, which in the long run could have detrimental consequences, but the sustainability in general was satisfactory. The levels of regeneration and recruitment were satisfactory. The health of the trees was improved; the stands were healthy, vital, and biologically and functionally stable. The study results point not only to a series of positive effects of the several-decades' long implementation of the Goc variety of the control method, but also to some problems, the understanding of which will have a corrective role in the future management of selection forests in western Serbia.