The forest management practices that were approved and implemented throughout the timber harvesting land base when the timber supply analysis was initiated are briefly described below.
• Basic silviculture - British Columbia laws require areas that are harvested and expected to produce timber in the future to be reforested with ecologically acceptable species within a specified time frame. The typical silvicultural practice is to: clearcut harvest; site prepare, if necessary; reforest by planting with a mix of species or by relying on natural regeneration; and control competing vegetation if needed. It is assumed that the majority of the harvested areas will be restocked within three to four years after harvesting. In some circumstances, such as high elevation sites, restocking may take five to seven years.
• Timber utilization - Within cutblocks, coniferous timber that meets or exceeds the following size limits and is suitable for the manufacture of lumber or pulp chips, must be utilized:
• diameter at chest height:
- lodgepole pine: 12.5 centimetres
- other coniferous species: 17.5 centimetres
• diameter at top: all species: 10 centimetres
• As no deciduous harvesting had occurred in the Fort St. John Timber Supply Area when the data was prepared for the timber supply analysis, standards from the Dawson Creek Timber Supply Area, where deciduous harvesting is occurring, were used. These standards are 12.5 centimetres at chest height and 10 centimetres top diameter. It should be noted that the current pulpwood agreement for deciduous harvesting includes a utilization standard of 17.5 centimetres at chest height.
• Roads and landings - Road building and harvesting layout follow provincial and regional guidelines. For the timber supply analysis, five per cent of the timber harvesting land base was deducted for roads and landings, and approximately 1.5 per cent was deducted for losses to oil and gas exploration.
• Forest health and unsalvaged losses - Forest losses due to wildlife, insects, diseases and blowdown are minimized as much as possible and damaged timber is harvested when feasible. Unsalvaged losses of merchantable coniferous timber are estimated to be 150,000 cubic metres per year, due to:
• fire - 137,000 cubic metres per year
• wind damage - 13,000 cubic metres per year
Estimates of unsalvaged losses for deciduous species are not currently available to incorporate in this review.
• Harvestable ages - Minimum harvestable age is defined as the time it takes for forests to grow to harvestable size which varies by tree species and site productivity. The minimum harvestable ages used in the timber supply analysis range from 60 to 140 years.
• Fish and wildlife/ biodiversity - Riparian buffer areas, where timber harvesting is restricted, are located along waterways to protect fish habitat and provide wildlife habitat. For the timber supply analysis, the timber harvesting land base was reduced by 1.5 per cent to account for these buffers. This area is in addition to the forested areas deducted from the timber harvesting land base, such as environmentally sensitive areas and forests that are uneconomical to harvest which also provide wildlife habitat and fulfill biodiversity management objectives.
In addition, the following practices contribute to general biodiversity and wildlife habitat: the forest cover requirements defined for each management zone; requiring regenerated forests on previously harvested areas to be at least three metres tall before the adjacent timber can be harvested; and, leaving deciduous trees in mainly coniferous forests standing after harvesting.
