In the U.S., any of numerous forest areas under federal supervision for the purposes of conserving water, timber, wildlife, fish, and other renewable resources and providing public recreation areas.
Administered by the U.S. Department of Agriculture's Forest Service, in the early 21st century the forests numbered 155 and occupied 352,000 sq mi (911,700 sq km) in 40 states and Puerto Rico. They were founded in 1891 as a system of forest reserves and were renamed national forests in 1907. See also Gifford Pinchot .