Note that the data published in the 2002 State of the Nation’s Ecosystems Report as well as the 2003 and 2005 Web-Only Updates have been superseded by the 2008 Report and thus should be used with caution. For the most recent data, purchase the 2008 Report from Island Press.

View Data for Forest Types

What Is This Indicator, and Why Is It Important? This indicator reports the acreage of a variety of forest “cover types.” Cover types describe the dominant species of trees found in the forests (e.g., oak–hickory forests are dominated by oaks and hickories, but include other kinds of trees as well).

Forest type may change as a result of direct human intervention (fire suppression, planting and harvesting, development, and grazing) or because of natural succession. Changes in climate may also affect the range of different forest types.

Different plants and animals live in different types of forests. In addition, the types of forest available influence the way people use them for recreation and other purposes.

What Do the Data Show? From 1963 to 2002, Eastern forest types increasing the most included oak-hickory (20 million acres, or about one-half percent per year) and maple-beech-birch (22 million acres, or about 2% per year); the only Western forest type increasing in that time period was fir-spruce (21 million acres, or about 1% per year).

In the East, longleaf-slash pine and lowland hardwoods (elm-ash-cottonwood and oak-gum-cypress) had the largest decreases in acreage from 1963 to 2002 (11 million and 15 million acres, respectively, or about 1% per year). Types decreasing the most in the West included, hemlock-sitka spruce (11 million acres, or about 1% per year), ponderosa pine (10 million, or about one-half percent per year), and lodgepole pine (5 million acres, or about one-half percent per year).

In the East, “nonstocked” land (land where trees have been cut but that has not yet regrown as forest) has declined steadily.

It is important to note that total forest area changed very little over this period. In general, the increases or reductions described here represent shifts from one forest type to another.