IntroductionThis article is part of a larger document. View the larger document here.
Forests cover a vast area of the United States: 303.1 million ha or approximately onethird of the Nation’s land (Smith and others 2004). These forests are of substantial ecological, economic, and social importance. Both their ecological integrity and their continued capacity to provide goods and services are of considerable concern in the face of a long list of threats, including insect and disease infestation, fragmentation, catastrophic fire, invasive species, and the effects of global climate change.