An accelerated decay test was set up to compare the performance of CCA-treated needle-incised white spruce and lodgepole pine heartwood with end-matched conventionally-incised material. Short lengths of 2 x 4 and comparable untreated material were installed in a warmed soil bed in the open air. After 12 years of accelerated exposure (equivalent to 15 years' natural exposure), all the treated material - spruce and lodgepole pine, needle and conventionally incised - was almost completely sound with minor patches of surface decay. In contrast, both the untreated spruce and the untreated lodgepole pine heartwood had failed due to decay. The performance of needle-incised and conventionally-incised lumber has been very similar in both species.
Preservation - Incising - Tests
Picea - Preservation
Pinus contorta Dougl. var. latifolia - Preservation