Glossary of "Environmental Science: Earth as a Living Planet (2nd ed.)" by Botkin & Keller (1998)
- Forestland believed or known to be an economically profitable source of timber, often defined as capable of producing at least 1.4 m3/ha (200 ft3/acre) per year of wood.
- Botkin, D. B. & Keller, E. A. 1998. Environmental Science: Earth as a Living Planet, 2nd ed. -xxxxii + 649 pp. John Wiley & Sons, Inc., New York.