Untapped volume of surplus forest growth as feedstock for bioenergy

In Canada, the annual allowable cut (AAC) sets the harvest limit of roundwood and aims to maintain the long-term productive capacity of the forest while taking into account other values such as biodiversity and needs of stakeholders. Current harvest levels in the province of Quebec, which feed an industrial network dominated by the production of lumber, panels and pulp, average only 55% of the AAC, which may cause a gradual depletion of the forest resource if stands that have the highest value are preferably selected. In this context, using surplus forest growth consisting of low quality trees and less desirable stands as bioenergy feedstock could help improve both silvicultural practices and wood value chain profitability. The aim of this study was to identify biophysical and socio-economic factors that affect the proportion of the AAC that is harvested in Quebec's 74 management units. Results from the analysis of AAC and harvesting data for the period 2008–2013 showed the harvested proportion of the AAC was particularly low for hardwood species, with the proportions for poplar, birch and maple ranging between 19 and 38%. The distance to the nearest pulp or particle board mill was confirmed as the prime factor determining the harvest/AAC ratio for deciduous species. For softwoods, the presence of deciduous stands in a given region affected the harvest/AAC ratio. Low quality hardwoods could be used as an important source of feedstock for the bioenergy sector. Developing a synergy between conventional and bioenergy products could facilitate the application of sound silvicultural practices and increase profitability along the entire wood value chain.