Biological diversity, or biodiversity, is the full range of living organisms, in all their forms and levels of organization, and includes the diversity of genes, species and ecosystems, and the evolutionary and functional processes that link them. A major consideration in managing for biodiversity is leaving sufficient, and appropriately located, mature forests for species dependent on, or strongly associated with, old growth forests. Under the Code, a biodiversity guidebook has been approved recently that addresses stand and landscape-level biodiversity needs for a variety of ecological units found within the province.
The Code was not in effect when the timber supply analysis was undertaken for the TSA and therefore the base case does not specifically account for potential volume or land base reductions due to stand and landscape-level biodiversity factors. However, the various reductions made to define the timber harvesting land base identify the potential availability of about 243 000 ha (46 percent) of productive Crown forest area to help support old-growth needs for biodiversity under current management.
Since the timber supply analysis was completed, harvesting methods have been modified in some areas to support stand-level biodiversity objectives that include leaving high stumps and wildlife trees in clearcut areas, retaining patches in some harvest areas, and the establishment of Douglas-fir reserves in the Montane Spruce biogeoclimatic zone. A landscape-level biodiversity plan is being implemented on a pilot basis in the Yalakom Local Resource Use Plan area through the design and application of a forest ecosystem network.
BC Environment's submission notes that the base case does not explicitly address biodiversity. Its authors estimate that under current Code requirements, stand-level biodiversity practices will reduce the annually available volume by about 5000 m³ to account for wildlife trees, patch retention, and Douglas-fir reserves, and that there will be an unquantifiable impact from the leaving of high stumps. BC Environment staff indicate that they select decayed trees for high stumping, and that these trees may already be excluded from the timber supply analysis in allowances for decay, waste and breakage. More work is needed to verify that the high stumps left for stand-level biodiversity involve wood that is not assumed to be usable, in order to better assess timber supply impacts. BC Environment's estimates of impacts on timber volumes have been developed in consultation with Lillooet Forest District staff. While there is some uncertainty associated with these estimates, they constitute the best available information at this time and permit some accounting, in this determination, of the impacts on timber supply from provisions for biodiversity.
The CLMA submission suggests that the large area of productive forest land in the TSA that is not assumed to be part of the timber harvesting land base contains a broad spectrum of sites and species categories found within the TSA, and that this area will largely be old growth and can contribute to meeting non-timber resource objectives. The CLMA sees no justification for cover requirements for older-forest retention or extended green-up periods on the harvesting land base when 50 percent of the productive forest land of the TSA is considered unavailable for harvesting. While I agree that this forest will contribute to meeting objectives for other values, its ability to provide the required distribution of forests of different ages cannot be assured without addressing related spatial issues.
I acknowledge that more explicit provisions are needed to model the implications of managing for biodiversity in the future, such as the need for old-growth management areas and forest ecosystem networks distributed across the landscape. However, it is not possible for me to speculate at this point on the impacts that possible new provisions for planning for landscape-level biodiversity will have on timber supply. The Code requires consideration of biodiversity during forest planning, and enables the development of biodiversity objectives. Until clarity is provided on the objectives for biodiversity, through plans developed in accordance with the Code, and on the extent to which protected areas, riparian reserves under the Code, and other forests that are not in the timber harvesting land base can contribute to meeting those objectives, I cannot speculate quantitatively on the impacts. It is hoped that the LRMP process will assist in the development of objectives for biodiversity. Following the LRMP process and implementation of the Code, the next timber supply analysis conducted for the Lillooet TSA should be in a better position to examine any new requirements for biodiversity and to assess with more precision their implications for timber supply.
For this determination, I have considered the estimated timber supply impact of 5000 m³ annually for stand-level biodiversity to be a downward pressure on the short term timber supply, and I note that there will be an unquantifiable impact from future provisions for landscape-level biodiversity. These considerations are reflected in my "Reasons for decision".