This map displays the ecological division by color while delineating ecological provinces, sections and subsections for the conterminous United States. It is indented to provide a reference map of the ecological boundaries. The dataset was issued in 2007 by the USDA Forest Service Washington Office-Ecosystem Management Coordination staff. The data was compiled at 1:500,000 to 1:1,000,000 scales in participation with Federal and State agencies and nongovernmental partners. The polygon descriptions are presented for the delineated 190 section ecological units. Brief descriptions of the section map units provide an abstract primarily of the climate, physiographic, and geologic substrate that combine to form ecosystems with distinctive vegetation and other unique ecological characteristics.