Study of natural forest dynamics in the southern boreal forest has enabled us to establish the presence of two processes that may be essential for maintenance of biodiversity and long-term productivity: temporal replacement of species and the presence of a natural mosaic of stands at the landscape level. These two principles should form the basis for a new
silvicultural approach for mixedwood sites of this area, and should be applied in a flexible manner in order to take operational limitations into consideration. Strict regulation and silvicultural norms should be avoided and variations in scenarios should be advocated. Nature itself behaves with considerable variation and should inspire different silvicultural
interventions. For example, it would be inappropriate to prescribe partial cuttings in intolerant hardwood stands in which the softwood understorey was absent or very sparse. Also, self-replacement of hardwood stands does occur in nature after fire The same is true for the maintenance of the natural mosaic of stands at the landscape level. As has been
mentioned, the natural fire cycle has varied considerably over the last 8000 years; consequently, a certain variability exists within which organisms can easily adapt.