Durability of thermally modified balsam fir and eastern hemlock

Abstract

Hazardous fuels such as woody biomass and small-diameter trees accumulate in the forest, contributing to increased risk of wildfires. Two tree species that specifically contribute to this problem in the Midwest and Northeast of the United States are balsam fir and eastern hemlock. If the durability of these two species against fungal decay could be improved, markets for lumber made from these species would increase, contributing to removal of them from the forests. Thermal modification of the wood from these species may improve the fungal durability. In this study, we performed soil-block tests on specimens cut from thermally modified wood of these two species. The fungal species used were two brown rot fungi, Gloeophyllum trabeum and Postia placenta, and two white rot fungi, Trametes versicolor and Irpex lacteus. The soil-block tests showed that the thermal modification treatments improved the fungal durability of both wood species for all species of fungi.

Citation

Aro, M.; Bishell, A.; Kirker, G. 2021. Durability of thermally modified balsam fir and eastern hemlock. Research Note FPL-RN-0404. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 5 p