How can we feign sustainability with an increasing population?

Attitudes of human societies toward tree plantations can be a critical fact or in determining the source of wood supply in the future. Because human po pulations will expand substantially in the next century, considerable incre ases in the demands on native forests will occur. Currently, only a limited amount of tree plantations have been established specifically to provide f irewood in developing countries. This may be the result, in part, of a worl d society that has evolved a general preference for pastures, but an aversi on to tree plantations. In total, pastureland and tree plantations amount t o 26 percent and 1 percent of the world's land base, respectively. Neverthe less, our actions today will determine whether children in the future colle ct firewood from natural stands or from tree plantations. It is estimated t hat a substantial afforestation program could increase the amount of tree p lantations to equal 5 percent of the world's land base by the year 2050. Te n billion dollars (United States) is a rough estimate of the annual costs f or such a program (assuming no overhead or administrative costs). Most of t he wood needs could be met from tree plantations. However, if the world's s ociety wants most of its wood in 2050 to come from natural stands (> 80 per cent), then tree plantations can be limited to just 1 percent of the land b ase.