Forest Investment Account (FIA) - Forest Science Program
FIA Project Y103280

    The ecology and management of dry Douglas-fir forests: The Opax Mountain Silvicultural Study
Project lead: Andre Arsenault (Ministry of Forests and Range)
Author: Arsenault, Andre
Subject: Forest Investment Account (FIA), British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
The Opax Mountain silvicultural systems study is a long-term, multi-disciplinary, multi-agency research study of the ecological impact of alternative harvesting practices on a dry Douglas-fir forest in the Interior. The project was initiated in 1992 to provide information on the sustainability of different silvicultural systems. High priority information needs included: harvesting cost and operations logistics, forest regeneration; nutrient cycling and soil productivity; pest management; floral and faunal diversity, and historical patterns of natural disturbances. Considerable progress has been made in fulfilling these needs. Support for the Opax Mountain project is strong because it has already provided useful information to forest managers and planners particularly in the area of tree regeneration in patch cuts, soil productivity, natural disturbance regime and biodiversity. This study is well linked to several key projects in the IDF and constitutes a superb demonstration site, which has already been visited by over 1000 people including scientists from Canada and eight other countries. The location of Opax Mountain within the traditional territory of the Shuswap First Nation, and its close proximity to TRU, the Isobel demonstration forest and the McQueen Lake environmental centre and the city of Kamloops, make it an ideal demonstration area. Our extension activities are geared at not only current forest managers but also at forest managers of times to come whether they are enrolled at BCIT, NVIT, UCC, UBC, UVIC, SFU, TRU or whether they are in grade 1 of the elementary school program. This will not only assist us in promoting sustainable forest management but also at helping in the sustainable training of natural resource professionals. Our extension strategy includes a mixture of the World wide web, actual field tours, direct contact, and scientific publications to reach a diverse audience. So far the project has generated a large amount of public presentations, peer-reviewed scientific publications, and university theses. Our design incorporates the combination of a well replicated experiment, detailed monitoring, retrospective studies, and modelling which makes this project very strong. The main objective of this study is to evaluate the effects of six forest management treatments on a range of forest resources in Interior Douglas-fir forests. Stand regeneration is a fundamental requirement of a successful silvicultural system. The treatments have been therefore been designed to create a range of residual stem densities (% basal area removed: <20%, 35% and 50+%) and spatial characteristics (uniform removal vs. patchy). Consequently there is a range of canopy gaps (0.01 – 0.05 ha) in the partial-cut units and 1 – 4 tree heights wide (0.09, 0.36, and 1.6 ha) in the patch-cut units. These treatments, plus a control area of similar size, were applied in two different areas in a randomized complete-block design. One area has an elevation range of 950 – 1100 m in the IDFxh subzone, and the other, in the IDFdk subzone, has a range of 1200 – 1370 m. A range of site preparation methods were also applied at a small scale (in limited areas of each unit). The treatments and research focus on evaluating the costs and benefits of each treatment within an integrated resource management context. The main variables examined are soils, microclimate, tree regeneration, growth and yield, natural disturbance dynamics, and biodiversity (flora and fauna).
The second phase of the Opax Mt. project has been very successful at completing re-measurements for soils, vegetation, and regeneration and at publishing results and at initiating a synthesis of the project to date. Further work is needed to complete extension material on data being collected in 2006-2007 and for the re-measurements of wildlife response to treatments and changes in forest structure 12-15 year after harvest.

The work proposed for the final stage of “Phase 2” of the Opax Mt. project focuses on 3 general areas:
1. Completion of research reports and publications from data being collected in 2006-2007.
2. Re-measurements of wildlife response to treatments using permanent grids and assessing relationship between biodiversity and stand structure created in a variable retention system.
3. Update of the Opax Mountain interpretive trail.
Related projects:  FSP_Y081280FSP_Y092280


Opax Mountain final technical report (0.4Mb)

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Updated August 16, 2010 

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