Samples of eastern wood species (balsam fir, black spruce, Jack pine and red spruce) from the SPF commercial species grouping were treated with high-temperature borate in a commercial trial at Légaré Industries, Quebec. The treated samples along with similar samples of untreated lumber were tested for bending strength and stiffness.
The results suggest that the high-temperature borate treatment does not have a significant effect on the mean modulus of elasticity of the lumber. However, there appears to be a reduction in the bending strength after treatment. The reduction is estimated to range from 0.65 to 0.85. Due to the imperfect matching of the treated and untreated samples (both in terms of grade mix and modulus of elasticity), further study is recommended.