Old-growth, disturbance, and ecosystem management: Commentary

Abstract

Johnson, Miyanishi, and Weir's (1995) suggestion that the concept of old growth should be based on landscapelevel properties as well as on properties within individual stands or ecosystems is a valuable contribution to our understanding of a complex forest management issue. I am, however, concerned that their discussion of the management implications of their work may lull some readers into-a false sense of security concerning the potential long-term ecological implications of fire suppression in the boreal forest region and foster significant misconceptions about Canadian forest fire management practices. Johnson et al. (1995) state that landscape-level processes may be beyond the manipulation or control of managers and cite current fire management and fire suppression in boreal and subalpine forests as examples. They say that the landscape age mosaic is largely determined by the fire cycle, which evidence suggests is controlled by climate. They go on to say . it may be virtually impossible, regardless of fire-suppression policies, to manipulate the fire cycle and hence the age mosaic of the boreal forest landscape. These statements may lead readers to believe that fire suppression does not have the potential to alter significantly the landscape age distribution of the boreal forest. The fact that weather has a very significant impact on fire in the boreal forest region of Canada is beyond dispute. The suggestion that fire suppression does not have a significant impact on burned area, however, is not. Johnson et al. (1995) refer to the boreal and subalpine forests and thereby imply their findings are applicable to all of those forests. I do not believe that is the case and I will present evidence to the contrary. I restrict my comments to that portion of the boreal forest that lies within the province of Ontario. The Ontario Ministry of Natural Resources (OMNR) uses a zoning scheme to guide the allocation of its fire management resources. ~hebor t ion of the province that is subject to fire management is partitioned into intensive, measured, and extensive protection zones.