One submission asserts the adjacency requirements are critical because a seven-pass system would mean a significant decrease in the harvest level, whereas a four-pass system would permit the base case harvest level. It is suggested that even a four-pass system has faults in that more mature timber that is susceptible to insects and disease is left standing.
Two submissions state the procedure for modeling adjacency constraints is unrealistic because a four-pass system is not equivalent to a maximum non-greened-up denudation of 25 per cent. One author writes that all multi-pass systems have higher proportions of the area harvested in the first pass. Because of past harvesting, the most critical time for meeting the maximum denudation constraint is in the first decade, when a higher percentage denudation should be used. Although many areas are planned on a three-pass harvest system, the analysis uses a four-pass system. (Two submissions on the data package support the use of a three-pass system.) The submission further asserts that suggestions that a seven-pass system should be considered are absurd because of the long rotations that would result. There is no biological evidence timber stands in the Prince George Timber Supply Area live much beyond 250-300 years, and at that age, mortality and decay have reduced the volume substantially.
