These agencies are as follows: Bureau of Land Management (BLM), 248.3 million acres; Forest Service (FS), 192.9 million acres; Fish and Wildlife Service (FWS), 89.1 million acres; and National Park Service (NPS), 79.8 million acres. In addition, the Department of Defense (DOD) administers 11.4 million acres in the United States, about 2% of all federal land. Conflicting public values concerning federal lands raise many questions and issues, including the extent to which the federal government should own land; whether to focus resources on maintenance of existing infrastructure and lands or acquisition of new areas; how to balance use and protection; and how to ensure the security of international borders along the federal lands of multiple agencies. Emphasis shifted during the 20 th century from the disposal and conveyance of title to private citizens to the retention and management of the remaining federal lands. As noted, DOD is the fifth-largest land management agency, with lands consisting of military bases, training ranges, and more. Numerous other federal agencies—the U.S. Army Corps of Engineers, Bureau of Reclamation, Post Office, the National Aeronautics and Space Administration, the Department of Energy, and many more—administer additional federal lands. In addition, the BLM administers about 700 million acres of federal subsurface mineral estate throughout the nation. These purposes were expanded in the Multiple Use-Sustained Yield Act of 1960. The FWS has a primary-use mission—to conserve plants and animals. The NPS has a dual mission—to preserve unique resources and to provide for their enjoyment by the public. Federal Land Ownership, 2015

The roughly 640 million acres of federal land in the United States represents about 28% of the total land base of 2.27 billion acres. Table 1 provides data on the total acreage of federal land administered by the four major federal land management agencies and the DOD in each state and the District of Columbia. These tables reflect federal acreage as of September 30, 2015, except that DOD figures are current as of September 30, 2014. The figures range from 0.3% of land (in Connecticut and Iowa) to 79.6% of land (in Nevada). Through the numerous individual acquisitions and disposals since 1990, the total federal land ownership has declined by 25.4 million acres, or 3.9% of the total of the five agencies, as shown in Table 3 . This increase was not uniform, with declines in some states and varying increases (in acreages and percentage) in others. Debates also encompass the extent to which federal lands should be developed, preserved, and open to recreation and whether federal lands should be managed primarily to produce national benefits or benefits primarily for the localities and states in which the lands are located. Advocates of retention of federal lands, and federal acquisition of additional lands, assert a variety of benefits to the public of federal land ownership. With regard to disposal, the NPS and FWS have no general authority to dispose of the lands they administer, and the FS disposal authorities are restricted. Western Land Concentration

The concentration of federal lands in the West has contributed to a higher degree of controversy over federal land ownership in that part of the country. Of the land in the 11 contiguous western states, 46.4% is federally owned, which includes 73.4% of total FS lands and 70.3% of total BLM lands. In the rest of the country, the federal government owns 4.2% of the lands, with 60.9% of those managed by the FS. Nearly half of this land (12.3 million acres) was managed by BLM, and the other federal lands were managed by DOD (5.8 million acres), FS (3.8 million acres), NPS (2.4 million acres), FWS (2.2 million acres), and other federal agencies (0.2 million acres). Differences in missions and jurisdictional complexity among these agencies have been identified as potentially hindering border control.
The federal government owns roughly 640 million acres, about 28% of the 2.27 billion acres of land in the United States. Four major federal land management agencies administer 610.1 million acres of this land (as of September 30, 2015). They are the Bureau of Land Management (BLM), Fish and Wildlife Service (FWS), and National Park Service (NPS) in the Department of the Interior (DOI) and the Forest Service (FS) in the Department of Agriculture. In addition, the Department of Defense (excluding the U.S. Army Corps of Engineers) administers 11.4 million acres in the United States (as of September 30, 2014), consisting of military bases, training ranges, and more. Numerous other agencies administer the remaining federal acreage.
The lands administered by the four major agencies are managed for many purposes, primarily related to preservation, recreation, and development of natural resources. Yet the agencies have distinct responsibilities. The BLM manages 248.3 million acres of public land and administers about 700 million acres of federal subsurface mineral estate throughout the nation. The BLM has a multiple-use, sustained-yield mandate that supports a variety of activities and programs, as does the FS, which currently manages 192.9 million acres. Most FS lands are designated national forests. Wildfire protection is increasingly important for both agencies. The FWS manages 89.1 million acres of the U.S. total, primarily to conserve and protect animals and plants. The National Wildlife Refuge System includes wildlife refuges, waterfowl production areas, and wildlife coordination units. In 2015, the NPS managed 79.8 million acres in 408 diverse units to conserve lands and resources and make them available for public use. Activities that harvest or remove resources from NPS lands generally are prohibited.
The amount and percentage of federally owned land in each state varies widely, ranging from 0.3% of land (in Connecticut and Iowa) to 79.6% of land (in Nevada). However, federal land ownership generally is concentrated in the West. Specifically, 61.3% of Alaska is federally owned, as is 46.4% of the 11 coterminous western states. By contrast, the federal government owns 4.2% of lands in the other states. This western concentration has contributed to a higher degree of controversy over federal land ownership and use in that part of the country.
Throughout America's history, federal land laws have reflected two visions: keeping some lands in federal ownership while disposing of others. From the earliest days, there has been conflict between these two visions. During the 19th century, many laws encouraged settlement of the West through federal land disposal. Mostly in the 20th century, emphasis shifted to retention of federal lands. Congress has provided varying land acquisition and disposal authorities to the agencies, ranging from restricted (NPS) to broad (BLM). As a result of acquisitions and disposals, from 1990 to 2015, total federal land ownership by the five agencies declined by 25.4 million acres (3.9%), from 646.9 million acres to 621.5 million acres. Much of the decline is attributable to BLM land disposals in Alaska and to reductions in DOD land. By contrast, land ownership by the NPS, FWS, and FS increased over the 25-year period. Further, although 15 states had decreases of federal land during this period, the other states had varying increases.
Numerous issues affecting federal land management are before Congress. These issues include the extent of federal ownership and whether to decrease, maintain, or increase the amount of federal holdings; the condition of currently owned federal infrastructure and lands and the priority of their maintenance versus new acquisitions; and the optimal balance between land use and protection, and whether federal lands should be managed primarily to benefit the nation as a whole or to benefit the localities and states. Another issue is border control on federal lands along the southwestern border, which presents challenges due to the length of the border, remoteness and topography of the lands, and differences in missions of managing agencies.