Each graphic is linked to its background information, called the technical notes. Animal production is included, but rangelands are not. Forests are defined by the Forest Service as lands at least 10 percent covered by trees of any size. The Great Lakes are part of this system. Definitions for the remaining three systems will be included in the full Report in 2001.
Measures are the specific variables to be reported for each property.
For example, recreation is one of the 12 major properties, and visitor-days is a measure used to report on it. These properties were selected to describe the use and condition of ecosystems.