Stand Development Modelling

Overview
Additional Stand Development Modelling Information
Current Focus Areas
Research and Development Highlights
Extension and Consultations
Recent Publications and Presentations
Ministry Contact

Overview

The Ministry of Forests and Range is responsible for ensuring a balance between economic, social, and environmental values. Success rests upon our ability to predict the state of future forests and develop legislation, policy, and regulations that are based on science.

The Stand Development Modelling group contributes to the sustainable management of British Columbia’s forest resources by developing reliable growth and yield decision support tools and scientific information. As the provincial government faces critical issues such as the impacts of the mountain pine beetle infestation and climate change, the Stand Development Modelling group continues to develop new model applications to support changing forest management and policy, forest research, and sustainable timber supply projections.

Stand Development Modelling group personnel conduct a wide variety of long-term model development projects to increase our understanding of complex stand structures. Recent examples include studies of light and tree growth interactions, and of windthrow. New knowledge and data from permanent sample plots are integrated into our models to refine forecasted yields.

The Stand Development Modelling group is at the leading edge of complex stand modelling. The Tree and Stand Simulator (TASS) model, for example, allows forest managers to predict tree growth and the dynamics of stand development. Researchers are currently refining and testing the next version (TASS III) that models complex structures found in uneven-aged and mixed-species stands. TASS and other components such as the Table Interpolation Program for Stand Yields (TIPSY), and a suite of linked modules that evaluates the effect of Silvicultural Treatments on Yield, Lumber Value, and Economic Return (SYLVER), estimate the size, volume, and wood quality of second-growth stands. Thus, the economic alternatives of various management regimes can be compared. The information provided improves the competitiveness of the forest industry by ensuring that management investments are cost-effective. Prognosis^BC predicts growth and yield for complex forests of the southern interior and could be linked to economic modules in the future.

With increasing emphasis in the Ministry on understanding ecosystem resilience and forest values such as habitat, biodiversity, and visual quality, stand development models provide integrated information for priorities such the Future Forest Ecosystems Initiative, implementation of the Forest and Range Practices Act (FRPA), and Timber Supply Reviews. They also support second-growth management, Forest Stewardship planning and evaluation, and ecosystem-based management implementation on the coast.

This web site is intended to provide resource professionals involved in growth and yield projections with relevant background information necessary to select an appropriate growth and yield system for a particular application.

Additional Stand Development Modelling Information

Stand Development Models

Model Comparison and Selection

Models:

Links to Models Not Supported by the Research Branch:

Current Focus Areas

Validating and calibrating growth and yield models against independent data to ensure the accuracy and precision of models.
Increasing the applicability of models to local conditions by incorporating additional species, stand types, environmental factors, biogeoclimatic zones, and a broad range of growing conditions and factors that affect yield.
Providing high-quality, responsive, and focused services to internal (Executive, Forest Practices Branch, Forest Analysis Branch, Economics and Trade Branch, and Regions) and external (academia and forest practitioners in industry and consulting) client groups. Extension activities include providing convenient and free access to models, training and supporting model users, disseminating new information and improvements at meetings and workshops, and advising decision-makers.
Refining models to incorporate new information and capabilities, such as light–moisture interactions, hardwood and mixedwood modelling, light estimates, windthrow, and crown, wood, and fibre characteristics.

Research and Development Highlights

Scheduled a BETA release of the new version of TASS (TASS III) for early 2008. This new version is designed to manage complex stand types, including those with multiple species (both coniferous and broadleaf), such as boreal mixedwood ecosystems, and stands with structural diversity. It will allow users to implement and grow complex silvicultural treatments and harvesting patterns. The new model includes a revised computer architecture that permits simulation of multiple canopy layers, has a user-friendly graphical interface, and will run on a laptop computer.
Parameterizing existing models to predict variables other than tree growth, such as: optimum light conditions for non-timber forest products (e.g., berry and mushroom production), range forage, or caribou lichen growth; forest carbon budgets; genetic worth (percent elevated gain); and the economic impacts of forest health outbreaks such as mountain pine beetle, spruce weevil, and Armillaria root rot.
Completed a second season of understorey regeneration measurements at two sites in order to understand the development of residual trees and regeneration following mountain pine beetle attack in thinned lodgepole pine stands.
Compiled and analyzed over 10 years of permanent plot data collected at the Pothole Creek Study Area. This research studies uneven-aged stand development in interior Douglas-fir forests.
Collaborated with the U.K. Forestry Commission in Edinburgh, Scotland to incorporate their windthrow model ForestGALES into TASS.
Initiated destructive sampling projects designed to provide data to support TASS tree-level parameterization for new tree species such as red alder and trembling aspen, and further refinement of previously calibrated species such as white spruce and lodgepole pine.
Re-measured and analyzed long-term research trials to provide data for the development of custom TASS model projections of operational silviculture site preparation and vegetation management prescriptions. Several projects are collaborating with the B.C. Ministry of Forests and Range, Forest Practices Branch, and the Pacific Forestry Centre, Canadian Forest Service.
Conducted field research to explore light dynamics, tree growth, and interspecific competition between lodgepole pine, white spruce, and aspen found in boreal and sub-boreal mixedwood stands of interior British Columbia.
Collected field micro-climate data across a variety of partial-cutting regimes and forest types to capture baseline data on light, temperature, and moisture for future model development.

Extension and Consultations

Consulting with the Forest Practices Branch on the development of partial-cutting guidelines for the FRPA Forest and Range Evaluation Program.
Future Forest Ecosystems Initiative, Technical Role—Advising on projecting forest development under changing climate scenarios; assisting with identifying priority research projects associated with the Initiative objectives.
Forest and Range Practices Act Forest Resource Evaluation Program (FRPA/FREP), Technical Support—Determining ways to evaluate the impacts of proposed Forest Stewardship Plans and new results-based management techniques.
Forests For Tomorrow, Technical Support—TASS III will be used to grow advanced regeneration to determine whether there will be a viable timber source in the future and to better understand and predict the quality of wood from post-harvest and post-beetle stands, particularly in areas managed for spruce.
Presentations on TASS III to forest practitioners in a variety of venues, including the Complex Stand Modelling Conference, February 2007 and the Timber Growth and Value Conference, February 2008, both in Smithers, British Columbia.
Formed part of the scientific organizing committee for the International Union of Forest Research Organizations (IUFRO) Conference on Wind and Trees, University of British Columbia Forest Sciences Centre, Vancouver, B.C., August 2007. [link]
Presented results and management implications of a study on Douglas-fir tree biology and stand development at the Pothole Creek Study Area to 100 forestry practitioners at the Southern Interior Silviculture Committee in September 2007.
Presented the keynote address at the IUFRO Conference on Ecological Complexity and the Applications of Stand Development Models in Sault Ste. Marie, Ontario, July 2007.
Presented a paper at the IUFRO conference on Forest Growth and Timber Quality: Crown Models and Simulation Methods for Sustainable Forest Management in Portland, Oregon, August 2007.
Data use agreements with a wide variety of research institutions, universities, stand management co-operatives, provinces, and states to obtain PSP and experimental plot datasets for model development, calibration, and validation efforts.

Recent Publications and Presentations

Byrne, K.E. and C.M. Di Lucca. 2007. Incorporation of windthrow modelling into TASS and TIPSY and its application into STEMS (Silviculture Treatments for Ecosystem Management in the Sayward). Presentation given at the Coastal Silviculture Committee Summer Field Tour, Campbell River, B.C., Jun. 21-22.

Byrne, K.E., S.J. Mitchell, T. Shannon, and C.M. Di Lucca. 2007. Integrating ForestGALES_BC with TASS/TIPSY growth and yield model. Conference on Wind and Trees, IUFRO, Univ. British Columbia Forest Sciences Centre, Vancouver, B.C., Aug. 5-9, 2007.

Comeau, P., P. Fielder, G. Harper, and K. Thomas. 2007. Assessing the competitive effects of red alder on coastal conifer plantations. FORREX Forest Research Extension Partnership. LINK Newsletter 9(1): 12-13.

Di Lucca, C.M. and J.W. Goudie. 2007. Variable retention yield adjustments in TIPSY. In Overcoming Obstacles to Variable Retention in Forest Management: Science to Management Forum Proc., Sep. 25-27, 2007. B.C. J. Ecosystems Manage. 8(3):69-72.

Di Lucca, C.M., S.J. Mitchell, and K.E. Byrne. 2006. Using TIPSY to evaluate windthrow effects on regeneration in variable retention harvests. B.C. Min. For. Range, Res. Br., Victoria, B.C. Exten. Note 77.

Goudie, J. and C.M. Di Lucca. 2007. Tree and Stand Simulator (TASS): History, structure, applications and future developments. Presentation given at: Science Seminar: Forecasting Change: Ecological Modelling and Ecosystem Productivity. CFS, Pacific Forestry Centre, Victoria, B.C. Jun. 7, 2007

Goudie, J., C.M. Di Lucca, K. Mitchell, R. Parish, C. Bealle Statland, K. Polsson, and D. Simpson. 2007. Tree and Stand Simulator (TASS): History, structure, applications and future developments. Seminar given to biometrics and forest mensuration professors and graduate students. University of British Columbia, Vancouver, B.C. Jan. 2007.

Goudie, J.W. and S. Stearns-Smith. [2007]. TASS-TIPSY advance growth and yield modelling in British Columbia. FORREX Forest Research Extension Partnership. In press.

Goudie, J. and S. Stearns-Smith. 2008. BC’s forest professionals get TIPSY (and TASS III). B.C. For. Professional. Jan.-Feb. 2008.

Harper, G. [2008]. Quantifying the branch, crown and bole development of Populus tremuloides Michx. from north-eastern British Columbia. For. Ecol. Manage. In Press.

Harper, G., R. Astrup, and D. Simpson. 2006. TASS III boreal mixedwood modelling: light and understorey tree growth. Poster presented at the Canadian Weed Science Society Annu. Gen. Meet. and Forestry and Industrial Symp., Nov. 29, 2006, Victoria, B.C. and at the Post Harvest Stand Development Conf., Jan. 31–Feb. 1, 2006, Edmonton, Alta.

Harper, G. and K. Polsson. 2007. Modelling boreal mixedwoods with the Tree and Stand Simulator (TASS). B.C. Min. For. Range, Victoria, B.C. Exten. Note 80.

Harper, G., K. Polsson, and J. Goudie. [2008]. Modelling vegetation management treatments with the Tree and Stand Simulator. The For. Chron. In press.

Mansfield, S.D., R. Parish, J.W. Goudie, K.-Y. Kang, and P. Ott. 2007. The effects of crown ratio on the transition from juvenile to mature wood production in lodgepole pine in western Canada. Can. J. For. Res. 37: 1450-1459.

Suárez, J.C., B.A. Gardiner, B. Nicoll, A. Achim, S.J. Mitchell, C.M. Di Lucca, and J.W. Goudie. 2006. The next generation of wind risk models for managing upland forests in Britain. Geographic Information Science - Fourth International Conf., GIScience 2006, Münster, Germany.

Thomas, K.D., G.J. Harper, P.G. Comeau, and P. Fielder. 2006. Effects of red alder on stand dynamics and nitrogen availability (EP1121.01). B.C. Min. For. Range Victoria, B.C. Exten. Note 76.

Ministry Contact

Jim Goudie, Stand Modelling Research Leader

Ministry contact: Jim Goudie.
Please direct questions regarding webpage to For.Prodres@gov.bc.ca
Updated February 2008