A comparison between high and conventional incision densities for improving preservative treatment of Douglas-fir heartwood lumber
S T Lebow, J J Morrell
Incising is required for the preservative treatment of most wood species from the western United States; however, there is considerable debate about the density of incisions required to achieve adequate treatment. Previous studies have shown that the incision effect on treatment is relatively narrow, suggesting that incision densities should be significantly increased over current practices and stimulating the development of at least 2 competing high density incisors. In this report, we compare ammoniacal copper arsenate and chromated copper arsenate treatment of end-matched Douglas-fir lumber incised using one of these high density incisors and a conventional lumber incisor. As expected, higher density incisions improved the depth and uniformity of treatment; however, even this process could not improve CCA treatment to the point where it would meet the American Wood Preserver's Association Standard for treatment of dimension lumber.