Malheur National Forest, National Forest in Oregon, United States.

Malheur National Forest spans across the Blue Mountains and displays a mix of high desert grasslands, sagebrush, and several tree species. The terrain shifts between open areas with low vegetation and forested sections filled with juniper, pine, and fir trees.

The forest was established in 1908 under President Theodore Roosevelt and takes its name from the Malheur River. The area had been shaped by human activity long before this formal designation.

The name comes from the Malheur River, French for "misfortune". The Forest Service manages the land for timber extraction, cattle grazing, gold mining and wilderness use, and the ranger district offices sit in John Day, Prairie City and Hines. Two designated wilderness areas, Strawberry Mountain and Monument Rock, are kept free of human intervention.

The forest is accessible via U.S. Route 395 running north-south and U.S. Route 26 crossing east-west. Ranger stations throughout the area offer information and guidance to help visitors explore the landscape safely.

High on a ridgeline just west of Clear Creek lies an Armillaria ostoyae fungus covering 2,200 acres, the largest known organism by area in the Northern Hemisphere. It was found in 2000 after trees began dying unexplainedly; its weight is estimated at 7,567 to 35,000 tons and its age at 1,900 to 8,650 years.