Relationship between stand density and value of timber assortments: a case study for Scots pine stands in north-western Poland

Abstract

Background: Stand density changes during forest growth. Various types and intensities of thinning operations can be applied in order to improve the volume of the remaining trees. It is not clear whether or not thinning results in better total volume increment although timber value is usually higher when thicker logs are obtained from trees. The objective of this study was to determine if Scots pine (Pinus sylvestris L.) stands of lower density would produce timber of a higher value than stands with a higher density and thinner trees. Methods: The research was carried out on 20 experimental plots in 81–90-year-old Scots pine stands, located in north-western Poland. The data obtained were used to simulate the logging of the trees into either 2.5-m logs or tree tops, which were classified into five quality classes of timber. The volume of each assortment was calculated, based on its dimensions, and the value in EUR was calculated. Results: It was found that the correlation between stand density and the total value of the wood was very weak and not statistically significant. However, taking each assortment separately, the values of sawmill wood, pulpwood and energy wood were significantly correlated with stand density. Conclusions: It was concluded that lower densities were more profitable for sawmill wood production, while higher densities might be more beneficial in biomass production.