Idaho National Forest in Idaho was established by the U.S. Forest Service on July 1, 1908 with 1,293,280 acres (5,233.7 km2) from the part of Payette National Forest. On April 1, 1944 the entire forest was combined with Weiser National Forest to establish the new Payette National Forest, and the name was discontinued.
References
Idaho National Forest Wikipedia(Text) CC BY-SA