ABSTRACT
As we have repeatedly stressed, a forest can produce many kinds of outputs--wood, water, recreation, wildlife, wilderness, and perhaps others. The volume or amount of output of every kind of output depends in large measure on the inputs of labor, capital, and management into the production function, which relates kinds and amounts of inputs to kinds and amounts of output. If two forest tracts seem to differ in their per acre output of some good or service, this may merely reflect the fact that the amount of inputs is greater on one than on the other. However, it is true that some forests will produce more output of one kind or another than will another forest, at the same amount and kind of inputs. It is also true that the output from some forests responds more generously to increased amounts of inputs than do other forests. It is perfectly possible to classify forests or forest sites according to their ability to produce one kind or another outputs or their productive capacity, under carefully defined conditions and amounts of inputs.
