Forest Investment Account (FIA) - Forest Science Program
FIA Project Y092078

    Modelling the impacts of silvicultural treatments on the wood quality of interior spruce
Project lead: Goudie, James (Ministry of Forests and Range)
Author: Goudie, James W.
Subject: Forest Investment Account (FIA), British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
Interior spruce (Sx) accounted for over 20% of the total volume harvested in British Columbia in the period April 2004to March 2005; this amount was second only to lodgepole pine (55%). As the catastrophic effects of the current mountain pine beetle (MPB) outbreak unfold, the areas managed for spruce will no doubt expand greatly to help diversify interior forests and stabilize timber supplies. The Forest For Tomorrow (FFT) program will provide substantial investment dollars to offset the short and long-term effects of the MPB epidemic through the establishment of new stands and the management of advanced regeneration. There is concern among experts, however, that the quality of the wood from these post-harvest and post-beetle stands could be substantially lower than historical levels if the management of second growth stands is not conducted with up-to-date information (Pollack et al., 1992; Middleton and Munro, 2002). Wood quality research is a high priority in the current Forest Science Program (FSP) call for proposals.

Stand density management can control important tree, log and fibre characteristics. For Sx, we do not know which silviculture regimes will generate the best wood at the lowest cost. Previous work in coastal Douglas-fir (Mitchell and Polsson, 1993), lodgepole pine (Middleton et al., 1995; Mansfield et al., in press) and coastal western hemlock (Goudie 2003) indicated that crown structure influences wood quality (density, strength and stiffness, and tracheid characteristics). We plan to test this hypothesis for Sx in the central and northern interior of BC. Middleton and Munro (2002) conducted descriptive research into the current resource of interior spruce and showed that rapid growth reduces relative density, suggesting that wide spacing may reduce wood quality for some products. Furthermore, we cannot predict if silviculture treatments that promote rapid growth have positive or negative impacts on non-timber values such as wildlife habitat. The Tree and Stand Simulator (TASS) allows us to build models of stand development that may be used to predict both timber and non-timber responses to treatment. We propose to develop models to predict wood quantity and quality of managed interior spruce under different silvicultural strategies.

This will be achieved by:
1. collecting new information on tree growth, yield, wood quality, and value;
2. fitting relationships to predict the quantity and quality of wood that can be used in computer models;
3. building on the TASS modeling framework developed by the MOF, by specifically adding data on interior spruce.

Our strategy to complete this project contains three elements:
1. We will build on existing work where possible. Several components needed to complete this project have been developed by other agencies. For example, the TASS model will provide the basis for the prediction method for this project. This model has been developed over the last 40 years with support from the MOF, FRBC, FIA, and other agencies.
2. We will collect new information where needed to fill important knowledge gaps. This includes basic crown and wood quality attributes, and growth rates of Sx trees in central interior locations.
3. We have formed a team of stakeholders and agencies that can help us develop the tools to complete this project. The information from this project could have significant impacts on the strategies used to regenerate future forests in the BC interior.

Literature cited:
Goudie, J.W. 2004. Modelling the impact of silvicultural activities on the wood characteristics of coastal western hemlock in British Columbia. pp. 528-536. In Fourth Workshop on the connection between silviculture and wood quality through modelling approaches and simulation software Edited by Gerard Nepveu. INRA, Nancy, France.
Mansfield, S.D., Parish, R., Goudie, J.W., Kang, K.-Y. and Ott, P. (in press). The effects of crown ratio on the transition from juvenile to mature wood production in lodgepole pine in western. Canada. Can. J. For. Res.
Middleton, G.R., Jozsa, L.A., Palka, L.C., Munro, B.D., and Sen, P. 1995. Lodgepole pine product yields related to differences in stand density. Forintek Can. Corp. Western Lab Special Publ. No. SP-35. Vancouver, B.C.
Middleton, G.R. and Munro, B.D. 2001. Second-growth western hemlock product yields and attributes related to stand density. Forintek Can. Corp. Forintek Can. Corp. Western Lab Special Publ. SP-41. Vancouver, B.C.
Middleton, G.R. and Munro, B.D. 2002. Wood density of Alberta white spruce - Implications for silvicultural practices. Forintek Can. Corp. Final report on Contract MDFP2700-01. Vancouver, B.C.
Mitchell, K.J. and Polsson, K.R. 1993. SYLVER: A decision-support system for silviculture. In Les modeles de croissanceforestiere et leurs utilisations = Forest growth models and their uses Edited by Chhun-Huor Ung. Natural Resources Canada, CFS, Sainte-Foy, Quebec pp. 34-44.
Pollack, J.C., Johnstone, W.D., Coates, K.D., and LePage, P. 1992. The influence of initial espacement on the growth of a 32-year-old white spruce plantation. BC Min. For., Res. Br., Res. Note 111. Victoria, BC.
Related projects:  FSP_Y081078FSP_Y103078

Executive summary (72Kb)

Updated August 16, 2010 

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