LONGITUDINAL GAS-PERMEABILITY MEASUREMENTS FROM EASTERN WHITE-PINE, RED SPRUCE, AND BALSAM FIR

The permeability of wood is an important factor hi drying, in pulping, and in the preservative treatment of wood because it is indicative of the ease with which fluids can be transported into or out of wood. Th e longitudinal superficial gas permeability of eastern white pine, red spruce, and balsam fir was measured in this study, Within each specie s the results were compared to determine if significant differences ex isted among trees, at differing heights within the trees, and between the heartwood and the sapwood of the trees. Overall, the superficial g as permeability was far larger in eastern white pine than in red spruc e or balsam fir, probably as a result of its basic structure or the le vel of resins and other extractives. Among-tree variation had a signif icant effect on the permeability of balsam fr and red spruce but not o n eastern white pine. Heartwood/sapwood permeability differences were significant in eastern white pine and red spruce but not in balsam fr. Height was not a factor with any species tested.