Lillooet district staff assessed the degree to which different forest types were in fact being utilized in the TSA in order to account for non-merchantable stands, sites with low timber growing potential, and deciduous types in the timber supply analysis. The BCFS analysis excluded 54 740 ha for non-merchantable stands
(e.g. open-growing Douglas-fir stands with very low timber volumes), 40 311 ha of low growing sites, and 2686 ha of deciduous types and non-commercial cover (brush) - or 97 737 ha in total.
Since the timber supply analysis, district staff have reviewed and refined these exclusions, resulting in the identification of 53 106 ha of non-merchantable stands, 28 514 ha of sites with low growing sites, and 2924 ha of deciduous and brushi.e. 84 544 ha in total.
The main difference is a reduction to the area of low growing sites. This is due to improved methodology which uses site index instead of site class to define these types. In total, 13 193 fewer hectares need to be excluded from the initial timber harvesting land base due to these factors. This change is discussed further under aggregate impact.