InTrans / Aug 14, 2018

Preservative Treatment Evaluation with CCA and ACQ-B of Four Appalachian Wood Species for Use in Timber Transportation Structures

This work investigates the treatability of four Appalachian hardwoods with the waterborne preservatives CCA-C and ACQ-B. Heartwood and sapwood of the species were investigated, at least initially, for all species. Six-inch-long nominal 2 by 4 samples of red maple, yellow-poplar, hickory, and beech were end-sealed and vacuum/pressure treated with a 1 percent active ingredient solution of ACQ-B or a 2 percent solution of
CCA-C. The pressure durations were varied as well as the temperature of the solution (for ACQ-B). Measurements were taken of minimum and maximum penetration, percentage of cross-sectional area penetrated, and retention of preservative as determined by x-ray fluorescence spectroscopy. The sapwood of yellow-poplar and red maple was found to be 100 percent treatable. Hickory sapwood was consistent in treatability, although limited, while beech sapwood fell somewhere between hickory and the other species. Statistical analysis indicated that the duration of pressure periods used in this study had no consistent positive effect on treatment. The preservative solution was a significant factor in improved measures of treatability in some instances.