Research about silviculture first began in B.C. in 1928. Since then, a network of long-term experiments has been established, many of which continue to provide data and information important to addressing new and emerging issues for resource management in B.C.
Planting density has large potential impacts on amount, size and value of timber harvested from managed forests and on biological and technical rotation lengths.
Terminology such as “pre-commercial thinning”, "juvenile spacing", and "spacing" generally refers to cutting or tree removal in immature stands with the objective of reducing stand density to stimulate the growth of the remaining trees.
Some forests grow where important nutrients limit tree growth. Fertilizing forests with those nutrients is a proven method to increase tree growth, resulting in greater stand volume, greater carbon storage and reduced harvest ages. Understanding where nutrient deficiencies occur and how trees respond is an important focus of fertilization research.
Pruning removes the lower branches of tree stems and allows high value knot-free wood to develop. However, pruning is a very costly silvicultural treatment and the biological factors affecting the development of pruned stands must be understood to ensure that the investment returns are maximized.
Commercial thinning is an intermediate treatment where some trees are harvested for useful products while other trees are left to continue growing. The choice of which trees to harvest and which to leave will affect the resulting stand growth and volume of timber available at the final harvest. Research is needed to determine the best options for achieving stand management objectives.
Broadleaves and Mixedwood Management
Broadleaf stands often regenerate naturally after a disturbance; however, pure conifer stands tend to have a higher commercial value. Mixedwoods, unlike pure stands, are composed by multiple tree species sharing the same area.
Broadleaves and mixedwoods are a significant part of B.C.'s forested ecosystems, offering shelter and forage for many wildlife species and contributing to the overall biodiversity of this unique province. In addition, they are a renewable resource that provides employment opportunities now and in the future. Our research concentrates on interactions between various broadleaf tree species and the surrounding vegetation.
In British Columbia there has been a significant investment in terms of both money and time in the establishment, maintenance and measurement of a multitude of long-term silvicultural systems research trials.