Discarded small-logs recovery from natural forests: improving the value chain

Abstract
This study investigates how small logs from native trees, which fail to meet standardsawing criteria, can be utilized to enhance their value by producing solid wood for directuse or remanufacture rather than being relegated to biomass or fuelwood. We analyzeda sample of 177 small, discarded logs from native species from second-growth forestsof Nothofagus in the Ñuble Region, Chile. The logs were scored after a qualitative andquantitative assessment for small logs, as designed in this study, and processed usinga flexible sawing pattern to optimize wood recovery based on random lengths, widths,and thicknesses. Log dimensions varied, with lengths from 31 to 156.2 cm, small enddiameters from 11.5 to 25.6 cm, and volumes between 0.001 and 0.092 m3. Key defectsin logs included knots (95%), curvature (79%), and checks (46%), among others. A keyresult is the obtained general yield value of 36%, a considerable value for small-diameter,low-quality logs. The highest sawing yields were achieved with Nothofagus dombeyi (Mirb.)Oerst (42%), Geviuna avellana Molina and Persea lingue Miers ex Bertero Nees (39%), andNothofagus obliqua (Mirb.) Oerst (34%). The quality of the boards correlates positively withthe quality of the logs, and the yields with the log size and quality. The yield achieved inboards coming from such low-quality logs shows a promising possibility of improvementfor this kind of process. Further development of the grading process and automation of thesawmill process could be future research steps.
Description
Keywords
Native forest, Small logs, Carbon stock products, Remanufacture, Log yield
Citation