Abstract:
Understanding how silvicultural treatments and changes in the forest resource will affect wood quality characteristics, including
heartwood natural durability, is a critical need for forest managers. Because heartwood properties can be affected by
environmental disturbances, including silvicultural practices used to grow trees faster, we need to know if increased growth rates
have associated tradeoffs with natural durability. In this study, the effects of thinning and fertilization were studied on 24 western
redcedar trees that were part of a silvicultural trial. There was no consistent relationship between growth rate and extractive
content within trees and the fertilization and thinning treatments had no significant effect on the average extractive levels of the
trees. The physiological state of the tree, as represented by sapwood reserve levels, was weakly related to heartwood extractive
concentration (r2 = 0.26). Further studies to better understand the relationships between silviculture, heartwood extractives, and
natural durability are discussed.
