Baah-Acheamfour, M.; Schoonmaker, A.; Dewey, M.; Roth, B. Lodgepole Pine and White Spruce Thinning in Alberta―A Review of North American and European Best Practices. Land2023, 12, 1261.
Baah-Acheamfour, M.; Schoonmaker, A.; Dewey, M.; Roth, B. Lodgepole Pine and White Spruce Thinning in Alberta―A Review of North American and European Best Practices. Land 2023, 12, 1261.
Baah-Acheamfour, M.; Schoonmaker, A.; Dewey, M.; Roth, B. Lodgepole Pine and White Spruce Thinning in Alberta―A Review of North American and European Best Practices. Land2023, 12, 1261.
Baah-Acheamfour, M.; Schoonmaker, A.; Dewey, M.; Roth, B. Lodgepole Pine and White Spruce Thinning in Alberta―A Review of North American and European Best Practices. Land 2023, 12, 1261.
Abstract
A significant portion of the harvested land base in western Canada is becoming old enough or entering a phase where thinning is a legitimate option. A comprehensive review of the existing knowledge of commercial thinning (CT) treatments applied to pine and spruce-dominated stands in Alberta was conducted, with particular regard to the intensity, the timing of interventions, method and impacts on crop tree growth responses. Although the geographical focus of this review is Alberta, information on this topic is more complete in other areas of North America, and Europe, where there is a long history of density management. In areas of eastern North America, our review revealed that CT from below, with tree removal levels from 27 to 43% of the basal area could increase the merchantable wood volume from 11 to 60 m3 ha-1, depending on stand age and intensity of thinning. For Alberta conditions, and considering the risks, we conclude that commercial thinning basal area removal should be in the range of 25 to 40%, depending on a variety of factors such as species, wind firmness and insect or disease incidence and risk. Thinning too aggressively and/or too late will increase the blowdown risk but the literature is fairly consistent in suggesting that live crown ratios should be >40% to maximize the chance of growth response and minimize the blowdown risk. In cases where stands are also threatened by stressors such as drought, wind, and insect or disease outbreaks, CT treatments likely offer the potential at limiting the overall risk, but localized knowledge and experience are critical. It is intended that the information presented may support ongoing and future research trials and growth and yield (G&Y) model development with regard to potential CT treatments to apply and the likely results of practical application to commercial forestry.
Keywords
basal area; commercial thinning; crown ratio; density management; pine; spruce
Subject
Environmental and Earth Sciences, Ecology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
