Rangelands Information Text Version EMAP defined rangelands as terrestrial systems characterized by a climate regime where the potential evapotranspiration exceeds precipitation, annual precipitation ranges from less than 5 to 60 centimeters, and air temperatures range from -40 to 50 degrees centigrade. The vegetation is dominated by woody shrubs, grasses, cacti and leaf succulents, and drought resistant trees. The target population for rangeland sampling included the arid, semi-arid, and subhumid regions of the conterminous United States. Rangelands include desert scrub, prairies, grasslands, chaparral, open woodland, alpine tundra, arctic desert, and riparian communities but excluded intensively managed agriculture such as irrigated farmlands.
Many individuals think of rangelands only as deserts.
As noted above, however, rangelands include a diverse set of resource classes. As with wetlands, rangelands have been converted into other land uses such as agriculture, especially in the subhumid region. In monitoring rangelands, EMAP used a hierarchical biogeographic classification system that allowed interpretations at multiple levels of biological organization.