exist. In the first option, entire stands are managed using long
production cycles, which extend well beyond the ages considered
optimal for tree growth. Alternatively, selected trees, or other
structural elements are retained in old-growth stands during
silvicultural operations, while the rest is managed on shorter
production cycles. This scenario is represented by the variable
retention approach described by Franklin et al. (1997).We use the
term production cycle instead of rotation, since the latter applies
strictly to even-aged forests, while the former may be applied to
individual trees and thus selection forests.