Treatability of plywood containing intermountain Douglas fir veneers
J N R Ruddick, A Walsh
Eighteen sheets of plywood were obtained which contained intermountain Douglas-fir veneers from two regions of British Columbia. Following pressure treatment with chromated copper arsenate (CCA type C) and ammoniacal copper arsenate (ACA) the preservative penetration and retention in individual veneers was assessed. It was concluded from the study that the intermountain Douglas-fir veneer could not be adequately penetrated by either CCA or ACA, although the degree of penetration achieved with ACA was better than that recorded for CCA. The preservative retentions measured were generally in excess of that required for plywood to be used in the preserved wood foundation system.