However, many forest species may have good viability also in forests without the full characteristics of natural forests, as long as they can find their key resources for survival and reproduction. We have seen that the managed forests of today deviate on a number of characteristics from natural forests, with respect to the underlying disturbance dynamics and turnover time between stand-replacing disturbance events, as well as in structural elements such as tree species composition, age classes, amount and quality of dead wood, and the very pattern of the landscape distribution of these structural elements. However, as has been well documented over the last few years, only very few and limited areas of natural boreal forests exist today in Fennoscandia (e.g., Aksenov et al. Of temperate broadleaved forests hardly any natural forests exist today (cf Andersson & Lofgren 2000).