British Columbia has significant areas of healthy and vigorous juvenile lodgepole pine, both pure and mixed with other species. Some areas, however, are showing a range of impacts by forest health agents, from light to severe. The Winter 2010 issue of Silviculture magazine presented two articles that raised concerns about the potential of lodgepole pine at, or near, the free-growing stage to reach forecast stand volumes at rotation. Lodgepole pine's vulnerability to a range of forest health agents, added to a potential gap in the mid-term timber supply following the mountain pine beetle infestation, has created a situation that requires attention.
British Columbia has significant areas of healthy and vigorous juvenile lodgepole pine, both pure and mixed with other species. Some areas, however, are showing a range of impacts by forest health agents, from light to severe. The Winter 2010 issue of Silviculture magazine presented two articles that raised concerns about the potential of lodgepole pine at, or near, the free-growing stage1 to reach forecast stand volumes at rotation. Lodgepole pine's vulnerability to a range of forest health agents, added to a potential gap in the mid-term timber supply following the mountain pine beetle infestation, has created a situation that requires attention.
The provincial government is developing a comprehensive approach that addresses different aspects of juvenile lodgepole pine performance. This summary describes six initiatives underway.
1. Monitoring the Performance of Juvenile Stands
After the mountain pine beetle epidemic and through impending climate change, monitoring juvenile stands is particularly critical to check expectations of growth rates and create a feedback loop for management decisions. Two branches in the Ministry of Forests, Mines and Lands (MFML)-Forest Analysis and Inventory, and Forest Practices and Investment-are developing an inclusive monitoring strategy for stands of all ages. The purpose of the monitoring is to:
- enable early detection of forest health concerns
- update forest inventories
- refine predictions of future forest harvest yields
- support planning of investments and helping adapt managed forests to climate change
- provide information to inform forest management decision-making
At this preliminary stage, the strategy will likely integrate three existing information sources of lodgepole pine growth performance:
- The RESULTS database ("Reporting Silviculture Updates and Landstatus Tracking System"), which captures silviculture survey data and updates stand inventories. Each year over 600,000 hectares of surveys are completed to monitor young stands;
- Mid-rotation monitoring data collected using the Forest and Range Evaluation Program's stand development monitoring (SDM) protocol, conducted after the free-growing stage is achieved for intermediate-aged stands, to check and report on changes in stand attributes since free growing (e.g., inventory label , site index , stand yield estimates, forest health pest incidence );
- Monitoring of all higher risk younger age class stands, both managed and unmanaged, through Change Monitoring Inventory plots for stands up to age 60, to assess growth trends against Timber Supply Review assumptions.
Impacts of the mountain pine beetle on young stands are also being monitored through information from a range of aerial and ground surveys and permanent sample plots. This monitoring is continuing in areas of the province where beetle mortality is still occurring.
2. Improving Forest Health Risk and Hazard Ratings, and Species Recommendations
To provide surveyors and resource professionals with access to the most current information, provincial and regional forest health specialists are updating forest health risk and hazard ratings and species recommendations that will reduce the risk of severe pest losses in young stands. This work includes:
- Updating current information on existing websites2 to point practitioners to the available tools and latest information. This will help ensure the most current information is used to develop and review stocking standards in Forest Stewardship Plans.
- Generating maps that spatially describe known pest hazards using the best available information.
- Translating recommendations into stocking standards guidance for incorporation into forest health strategies for Timber Supply Areas.
- Providing the necessary training and information resources for field staff to correctly identify forest health agents and prescribe the most appropriate management practices:
- Stocking standard training will be provided to Forest Stewardship Plan reviewers through two on-line training sessions scheduled for February 2011,
- Regional forest health training will be available to silviculture surveyors in 2011,
- Best management practices are being developed for three biogeoclimatic zones to guide practitioners to important considerations for forest health and species recommendations,
- SDM training will be provided across the province in all districts starting in 2011.
One example of a forest health risk and hazard rating that provides guidance in management of lodgepole pine is the Mackenzie Pine Stem Rust Management Strategy, which aims for best management of stands with comandra and stalactiform blister rusts and western gall rust in the Mackenzie Timber Supply Area. New information will be used to improve the strategy over time. Other hazard and risk ratings that are in development or are currently available are for western spruce budworm, tussock moth, spruce weevil, and yellow cedar decline.
3. Reviewing Minimum and Target Densities
Minimum and target densities for lodgepole pine are closely linked to stand productivity, wood quality, branch size, anticipated survival rates, and other factors. Higher densities for planting or freegrowing target levels may be required. Staff in the Forest Practices and Investment Branch will monitor and quantify the scope of this issue, and, if required, determine cost-effective methods to address planting increased densities.
4. Promoting Species Diversity
Species diversity is an important part of risk reduction, biodiversity and climate change adaptation and mitigation in forest management. In British Columbia, the Interior Cedar-Hemlock biogeoclimatic zone is currently experiencing a very high rate of forest health agent damage to lodgepole pine. Reducing the reliance on pine by increasing species diversity in this and other zones is subsequently very important for mitigating potential losses from pine damaging agents.
Practitioners need to take advantage of opportunities to maximize productivity through effective species selection and silviculture practices. Examples include regenerating lodgepole pine, where appropriate, as a component of a broader species mix, planting genetically improved white pine, and using stumping treatments in areas of high root disease. The MFML will be developing clearer direction on expectations and best practices from both the analysis of species trial summary reports and a species diversity project at the landscape level. Forest districts will also have access to planting diversity statistics from RESULTS to assist in identifying potential problem areas. In addition, SDM will provide valuable feedback on the performance of silviculture regimes in adapting to a changing climate.
5. Informing Current Practices From Long-Term Research Trial Results
New practitioners often have insufficient experience or exposure to the impacts of forest health agents on lodgepole pine. Practitioners must fully understand the implications of stocking standards and survey results on future forest conditions. Long-term research trials can provide significant insight to inform decisions and provide training to new practitioners, and to current practitioners needing a technical refresher or update. Two examples include:
- Experimental Plot 660 at Chilko Creek, established in 1967, provides an opportunity to compare performance of white spruce, Douglas-fir, and lodgepole pine at different establishment densities
- The Bednesti site preparation trial is providing detailed 22-year results on the development and impact of hard stem rusts on lodgepole pine performance.
Staff in the Forest Practices and Investment Branch will identify key long-term silviculture trial installations and conduct tours in 2011 with those who develop or review stocking standards in Forest Stewardship Plans.
6. Using Multi-Block Free Growing Assessments
The MFML is also considering the expansion of a pilot system that assesses free-growing status by grouping blocks together. A multiblock system can be used to ensure that productivity targets are met at the landscape level while allowing for some tolerances to natural factors at the stand level. The objective is to develop a simple multiblock system for provincial application.
These six initiatives are being implemented to comprehensively address the performance of juvenile lodgepole pine in British Columbia and address the following three goals:
- Implementation of a reliable monitoring strategy that will identify the necessary action to provide reliable timber supply projections and outcomes.
- Knowledgeable silviculture surveyors who can accurately detect, identify, and report forest health agents.
- Well-informed forestry practitioners who have access to the latest information on forest health hazard and risk to make appropriate management prescriptions.
1 "free growing stand" means a stand of healthy trees of a commercially valuable species, the growth of which is not impeded by competition from plants, shrubs or other trees;
2 Forest and Range Evaluation Program www.for.gov.bc.ca/hfp/frep/index.htm Silviculture Surveys www.for.gov.bc.ca/hfp/silviculture/Silviculture_Surveys.html Stocking Standards www.for.gov.bc.ca/hfp/silviculture/stocking_stds.htm