Characteristics assessment of aspen logs used in the production of matches
Abstract: Aspen (Populus tremula L.) accounts for about 2% of the total wood stock in Sweden. Sawmills use only a small part (about 5,000 m³fub) of round wood aspen per year. Since there are no Swedish gradings and design values for aspen, no aspen is used for structural purposes. This also applies to other hardwood trees in Sweden. Aspen is mainly used for pulp and paper with a mass consumption of 800,000 m³fub per year of which about 50% is imported. Most imported aspen is from Russia and the Baltics. The other major use of aspen is in match industries. Consumption for matches amounts to approximately 30,000 m³fub per year in Sweden. The aim of the research work was to increase knowledge on the wood quality of aspen used in the production of matches. Aspen (Populus tremula L.) logs were collected from two different sites in Sweden and a non-destructive tools weas used to estimate the modulus of elasticity in logs. To measure the dynamic modulus of elasticity (MOEdyn), Fakopp resonance log grader used. Other properties like density and moisture content were measure and were correlated with the MOEdyn values in order to identify the site that has a better log quality. Besides, horizontal and vertical variation of different wood properties were measured and compared within and between trees from two different sites in order to justify the variation of log quality. A total of 20 trees from Askaremåla and Vimmerby, Sweden were felled and used in this study. From each tree, 3 m long logs were sampled from each base, middle and top. After that, non-destructive evaluations were performed in those logs. Besides, 5 cm thick discs were collected in every tree height (base, middle and top) to measure horizontal and vertical variations. This study shows that there were differences in MOEdyn between and within trees. It was evident that trees collected from Vimmerby had a better log property than that in Askaremåla. Using non-destructive tools, it is possible to sort out quality logs for the production of Swedish matches.
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