Custer National Forest

Custer National Forest is located primarily in the southern part of the U.S. state of Montana but also has separate sections in northwestern South Dakota. With a total area of 1,188,130 acres (4,808.2 km2), the forest comprises over 10 separate sections. While in the westernmost sections, Custer National Forest is a part of the Greater Yellowstone Ecosystem, the easternmost sections are a combination of forest "islands" and grasslands. A portion of the forest is also part of the Absaroka-Beartooth Wilderness and constitutes over a third of the wilderness land. South of Red Lodge, Montana, the Beartooth Highway (U.S. 212) passes through the forest in route to Yellowstone National Park.

The eastern areas are dominated by large stands of ponderosa pine surrounded by grasslands, which are often leased to local ranchers for cattle grazing. A relatively rare type of small falcon known as the merlin is found here in greater concentrations than anywhere else in the U.S. Mule deer, antelope and elk are also found. There are few rivers and lakes and much of the eastern sections emphasize land conservation and work closely with logging and ranching interests.