Qualitative and value production of tree species in mixed spruce-fir-beech stands under the conditions of the Western Carpathians

Abstract Value production is one of the most important information for comparing different tree species composition and management strategies in forestry. Although the value production of forest stands is affected by various factors thinning can be considered as one of the most important one. This paper aims at the evaluation of qualitative and value production in mixed Norway spruce (Picea abies [L.] Karst.), silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) stands, which were managed by crown thinning for a period of 44 to 50 years and/or left to self-development. More than 1,500 individual trees aged from 61 to 132 years from 15 subplots established in western part of the Low Tatras Mts. and the Great Fatra Mts. in Slovakia were assessed. The proportion of stems in the highest quality A (stem quality classes) reached a low percentage, i.e. 12% in beech, 28% in spruce and 13% in fir out of the number of evaluated trees. The percentage of the highest quality log classes (assortments I + II) of beech ranged from 0 to 23% and of coniferous ones from 2 to 12%. Regarding the management method used, this percentage accounted for 0.1 to 23% for plot with self-development, whereas in plots with tending it was from 1 to 23%. Value production of coniferous tree species was always higher compared to beech, regardless of the management method. Regarding individual tree species, we found the highest value production in fir (81.4 € m−3) and the lowest in beech (46.5 € m−3).