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Forestry Management in British Columbia, Canada

The province British Columbia in Canada is known for its high biodiversity with over 185 wildlife vertebrate, 171 bird species, and a variety of conifer and deciduous trees . In forestry management, it is important to recognize the cumulative effects of habitat and environmental changes that have the potential to threaten BC forests. To look at sustainability in forest management requires comparing the ecological impacts of timber harvesting and natural disturbances, such as fire, insects and disease.

Threats to British Columbia forests

Fire

In the late 19th century and early 20th century, forest fires were viewed in an anthropocentric manner as a major threat to public safety, and a waste of timber that could be otherwise harvested for human use. While forest fires can have a significant negative effect on mature conifer stands, fire plays a key ecological role in Canadian boreal forest ecosystems. In addition to maintaining forest productivity, fire initiates and concludes vegetation succession, influences the age structure and species composition, keeps biodiversity high, modifies the distribution of insects and disease, influences nutrient cycling, maintains diversity, prevents soil erosion, and stabilizes ecosystems. The relationship between fire and stand (tree) development is complex and requires careful consideration.

Human Activity

Clearcut in Port Renfrew, BC

British Columbia is one of the worlds largest exporters of wood fibre. In 2015 it was reported that British Columbia forestry supports 145,800 jobs and 7000 businesses, with an annual revenue of 15.7 billion dollars. Nationally, Canada’s deforestation can be attributed to urban development of transportation corridors and recreation (19%), hydroelectric development (10%), the forestry sector (10%), and other natural resource extraction industries (8%). British Columbia enforces a cap on the allowable annual cut by setting the maximum amount of timber allowed to be harvested by each company. In the province, 8.1% of British Columbia is protected from harvesting, also known as protected areas.

Invasive Species

Invasive species are those that are not native to a region, and have the ability to displace local species and disrupt natural ecological processes. The mountain pine beetle has a significant negative effect on mature conifer stands . The occurrence of pine beetle outbreaks are influenced by warmer temperatures from mild winters which reduce the mortality of beetle larvae during the winter. From 1995 - 2005, British Columbia experienced a decline in the health of conifer trees that was found to be correlated with the increase in the proportion of beetle-attacked conifers. In addition to the mountain pine beetle, other destructive invasive species include bark beetles, douglas fir beetles, spruce beetles, spruce leader weevil, and western spruce budworm. Climate change impacts the distribution, life cycles, habitats, and mortality rates of these invasive insects. With a warming climate, there is a greater accumulation of the larvae of invasive species which increases the feeding and predation stresses on tree hosts. The impact from invasive species in British Columbia are both ecological and economic, due to the disruption of the timber supply available for harvest.

Managing British Columbia Forest Threats

Management of Fire

Natural wildfire provides many benefits to forest ecosystems such as forest succession, species longevity, stocking, biodiversity, pest control, and soil fertility. Human activity interrupts the natural impact of wildfires making them stronger and more detrimental to the forests. To mitigate the impacts of fire on the landscape, management techniques should reduce potential for fire-starters and increase the capacity for fire suppression. A common management method is called prescribed burning. Prescribed burning is done by intentionally setting fires in specific areas to promote the biodiversity and health of forests, while restricting the ability of it to have severe short-term socioeconomic impacts. In order to reduce the risk to resources, infrastructure, and public health, cut-block boundaries such as roads or skid trails are used as barriers.

Management of Human Activity

To address the anthropocentric impacts on forests in British Columbia, management needs to plan for the long term (100-200 years). The complexity of climate change and ecological systems means that management methods should extend to ecosystems in general, rather than only stands on trees. Management methods should also be multi-objective in practice in order to assess forest attributes such as biodiversity, timber production, carbon storage and recreation purposes.

A comprehensive management technique is called the Decision Support System (DSS). DSS outlines the complexity of actions with regards to forestry and addresses the consequences of different management techniques over a range of ecological, economic, and social indicators. This is done by highlighting potential conflicts, using a science-based framework, conveying knowledge about long-term dynamics of forest ecosystems, and providing guidance by projecting trends within indicators. Simulation models are useful to determine what the best method is for harvesting trees. These models can be used to maintain specific or at-risk ecosystem types by using scientific knowledge.

A provincial management method implemented by British Columbia is the Forest Practices Code. This code must be followed by all forestry companies and there are repercussions if rules of the code are broken. Penalties include fines, reduction of allowable size of clearcuts or the removal of a company’s ‘right to cut’.

A common resource management method used in many fields is the precautionary principle. The precautionary principle states that when the impacts of an action are unknown, the action should not be executed. Within this principle is the concept of sustainable development of natural resources which requires that the the stock of capital of a product be maintained, and only harvesting what is above the base-stock.

Landscape management is a technique for commercial forestry companies to implement by allowing for longer rotations between cutting. Depending on the characteristics of a region (ie soil productivity, topography, proximity to mills), certain areas can be managed specifically for intensive wood production, while leaving other areas untouched for regeneration. This technique requires the management of the entire forest, rather than an isolated section in order to take into account the social, environmental, and economic needs of a region

A stand of trees affected by Mountain Pine Beetles in Massachusetts, USA

Management of Invasive Species

Management for invasive species requires monitoring, modelling, and assistance in promoting migration and genetic diversity. In addition to this, reducing the amount of timber harvested will conserve the present stand of trees. Monitoring insect and disease occurrences over long periods of time gives a better understanding of the effects of climate change and how forests respond to it. The information from monitoring can be used to model and forecast the range of potential future changes with indicators such as volume harvested, gross profit, ecosystem carbon storage, age-class distribution and patch-size distribution. The data from monitoring and modelling can be used to determine which tree species to breed or reintroduce in an area in order to increase tree stand resilience and reduce susceptibility to invasive species.