Harvesting practices for steep slopes
Much of the timber harvesting land base within the Lillooet Timber Supply Area is very steep, often with unstable, sensitive soils, making traditional ground-based harvesting methods environmentally unsound. Non-conventional harvesting methods such as helicopters or skyline systems may make it possible to harvest these areas without detrimental environmental impacts. These systems also require less road construction. This would increase the timber harvesting land base and the available mature timber.
Intensive silvicultural treatments
Few regenerated stands have grown to maturity in the Lillooet Timber Supply Area, or in the interior of British Columbia, making it difficult to estimate the amount of merchantable timber that can be expected from these areas. There are opinions that planting and stand tending practices (juvenile spacing, fertilization, etc.) may produce a growth rate for regenerated forests that is higher than the estimates used in the timber supply analysis. This may result in an increase in timber supply.
A test of the possible impacts of a 10 per cent increase in the growth of regenerated stands in the Lillooet Timber Supply Area indicated an increase in the long-term timber supply can be expected in about 80 years but the projected short-term timber supply did not change (TSAR page 27). The impacts of a larger increase in the growth rate of regenerated stands was not tested. Expecting a larger increase may not be realistic given the influence of factors such as root rot and the need to manage for biological diversity in plantations.
The Timber Supply Review was designed to assess the timber supply impacts of current practices. As a result, the range of intensive silvicultural treatments that might be implemented in the Lillooet Timber Supply Area was not examined. Further analyses are required to examine the potential opportunities for intensive silvicultural treatments and the implications of those treatments on timber supply and other resources.
Commercial thinning
The feasibility of commercial thinning in the Lillooet Timber Supply Area is limited by the area of younger forests and the steep slopes. Approximately 10 per cent of the timber harvesting land base has forests between 40 and 80 years old which might be candidates for commercial thinning. Only a small portion of these forests are on gentler slopes where commercial thinning may be possible.
