National Forest
There are 4,431,720 acres (17,934.535 km2, or 6,924.563 sq mi) of National Forest land within the county, more than in any county (or borough) outside of Alaska. National Forests and their acreage within the county are: Nez Perce National Forest 2,224,091; Clearwater National Forest 870,807; Payette National Forest 804,853; Bitterroot National Forest 464,108; Salmon National Forest 66,074; and Wallowa National Forest 1,787. The Nez Perce National Forest is located entirely within the county's borders, and is the largest National Forest lying within a single county.