The technical critique confirmed the Timber Supply Review analysis results, but generated new timber supply forecasts by examining the following issues:
• the size of the area attributable to problem forest types impacts both short- and long-term timber supply
• the short-term harvest level is very sensitive to the minimum harvestable age used
• old-growth site productivity estimation impacts the medium- and long-term timber supply levels
• The technical critique suggests that while an initial harvest reduction is necessary to provide acceptable future timber supply patterns, this reduction can be limited to five per cent, permitting an initial harvest level of 551,000 cubic metres for the next 10 years. The harvest would then decline to 476,000 cubic metres over the next two decades before increasing to a long-term timber supply level of 481,000 cubic metres in 60 years. This represents an increase of nine per cent in the long-term timber supply level compared to the Forest Service analysis. The reasons for this increase are:
• the timber harvesting land base increased when different criteria were used to define problem forest types
• increases in future forest volumes resulted from an old-growth site productivity adjustment which reduced minimum harvestable ages
• increased long-term volume expectations for cedar, hemlock and spruce
The technical critique suggests maintenance of timber supply levels identified in this analysis over the first eight decades is dependent upon the availability in decade eight of stands which are being grown now. If these forests are not suitable for harvesting 80 years from now, there will be a significant shortage of wood. This sensitivity arises from the current age class distribution of forests in the Soo Timber Supply Area and is indicated in both the technical critique and the Forest Service analysis.
With the exception of suggested changes in the timber productivity estimates for regenerated forests and of the criteria to determine problem forest types, recommendations were not provided to improve the data, assumptions or computer model used in the Forest Service analysis.
