Nondestructive testing (NDT) of wood products, such as lumber and veneer, for stiffness and strength evaluation has been proven and commercialized for many years. The NDT concept has been extended and commercialized in the Director HM-200™ tool for testing logs in advance of processing so manufacturers can make more informed log purchases and better match logs to customer needs for product stiffness and strength. Further extension of the NDT concept to standing timber is a logical progression and a new commercial tool, the Director ST-300™, has just been developed for this application. This paper describes operating principles of both tools and presents examples of their use with various species. The potential effects of wood density, moisture content, temperature, and age on results from these tools are also discussed.
Carter, Peter; Briggs, David; Ross, Robert J.; Wang, Xiping. 2005. Acoustic testing to enhance western forest values and meet customer wood quality needs. Productivity of western forests : a forest products focus. Portland, OR : U.S. Dept. of Agriculture, Forest Service, Pacific Northwest Research Station, . General technical report PNW ; GTR-642.