Based on a study conducted by researchers with the Canadian Forest Service, FPInnovations and the ministère des Ressources naturelles et de la Faune du Québec, genetic selection of white spruce for wood volume only tends to produce trees that, when young, have poorer mechanical properties. Wood obtained these 30-year-old genetic trials was found to have reduced density, numerous knots, and a high proportion of juvenile wood.    

In the scientific literature, these factors are recognized as having a negative impact on mechanical properties. Wood with these characteristics has a low modulus of elasticity and a low modulus of rupture, making it generally unsuitable as a construction material for light structures. However, as the trees age they will have a greater proportion of mature wood, thus enhancing their mechanical properties.

Although volume gain has always been a primary objective of breeding research, researchers believe that wood quality could also be improved by selecting trees with proportionally fewer branches. With fewer and smaller knots, the wood would have better mechanical properties. Therefore, the inclusion of wood properties in selection criteria should make it possible to produce higher value wood.

This research was conducted following commercial thinning operations carried out in two 36-year-old white spruce plantations.