Growth and basic wood properties of black spruce along an alti-latitudinal gradient in Quebec, Canada

Abstract : The Canadian forest industry is turning its attention towards the unmanaged areas at higher latitudes, where the forest resource is still poorly understood because of lack of accessibility. Despite a lower productivity in terms of volume, northern stands are expected to produce wood of higher quality, which may make these areas attractive for management and production. This study aims to test the hypothesis that trees at high latitudes produce wood with better basic properties than trees at lower latitudes. Growth and wood characteristics were assessed according to cambial age in 25 black spruce (Picea mariana) trees from five sites located along an alti-latitudinal gradient in Quebec. Sites at higher latitudes and altitudes exhibited slower growth rates and lower stem volume. Wood density and mechanical properties were higher in the sites located at lower latitudes or altitudes. Fiber size had higher values in southern sites, but only at younger ages. Principal component analysis confirmed these results, with the northernmost site being the one where growth, density and mechanical properties were generally lowest. The reduction in growth was not compensated by increases in the basic properties of wood.