Quantifying the implications of transformation from even to uneven-aged forest stands

Transformation requires, in part, the setting of goals for the stand structure that should be ultimately achieved. This structure can be described by the number of trees per unit area of different sizes, and their species, before and after the harvest. The structure should be sustainable under the prescribed intensity of harvest and cutting cycle. In addition, the harvest and residual growing stock should be such as to meet management goals in the best possible way. These goals usually involve economic and ecological dimensions that can be quantified with financial criteria such as net present value, and with ecological criteria such as diversity indices. The core of quantification is a growth model suitable for the specific forest type under consideration. The growth model allows the determination of feasible, sustainable regimes, which are rarely unique. The choice of a specific regime can be guided by optimization methods, for example, to maximize economic returns, subject to ecological constraints. Once the desired state is decided upon, the conversion to this state can be achieved by harvesting only the trees in excess of the desired distribution. Alternatively, the conversion can also be optimized, for example, by calculating the regime that brings the stand as close as possible to the desired state, within a specific amount of time.