The refractory heartwood of species such as spruce and lodgepole pine can now be treated to meet Canadian wood preservation standards. This is a consequence of a series of innovations in incising technology originating in the Pacific Coast region of North America. Double-density incising, developed by Forintek, coupled with the Gen II PermacisorR developed by B.C. Clean Wood Preservers Ltd. provides a sufficient density of incisions for spruce-pine-fir lumber to be effectively treated without destroying its surface appearance. However, drying to around 30% moisture content and pressure treating for longer than is commonly done at present will be required to meet the standards.