Title: Influence of Veneer Roughness, Lathe Check, and Annual Ring Characteristics on Glue-bond Performance of Douglas-fir Plywood Abstract approved; AN ABSTRACT OF THE THESIS OF

Current lathe technology, smaller diameter logs, smaller core diameters, and the sale of higher grade veneer for use in engineered wood products are all factors contributing to plywood manufacturers using rougher veneer with different lathe check characteristics. When rough veneer is encountered, plywood manufacturers typically increase the adhesive spread rate in an attempt to achieve sufficient bonds between veneer surfaces. However, the effectiveness of this practice has not been clearly established. Little is known about how veneer roughness and lathe check characteristics interact to determine glue-bond quality or how lathe checks propagate under load while contributing to glue-bond failure. It was hypothesized that veneer roughness, lathe check, and annual ring characteristics interact to determine plywood glue-bond quality (i.e., wood failure percentage and load at failure). This study investigated the influence of veneer roughness, lathe check, and annual ring characteristics on Douglas-fir Pseudotsuga menziesii) plywood glue-bond performance. The study also investigated the differences in glue-bond quality when Redacted for privac