Plumas National Forest  Plumas National Forest is a 1,146,000-acre (4,638 km2) United States National Forest located at the northern terminus of the Sierra Nevada, in northern California. The Forest was named after its primary watershed, the Rio de las Plumas, or Feather River. About 85% of Plumas National Forest lies in Plumas County, but smaller portions are found in eastern Butte, northern Sierra, southern Lassen, and northeastern Yuba counties. The land is managed by the United States Forest Service under the Department of Agriculture with local management stationed at the Plumas National Forest Supervisor's office in Quincy, California. The forest is also subdivided into three Ranger Districts, the Beckwourth Ranger District, the Feather Falls Ranger District and the Mt. Hough Ranger District, with local management in Blairsden, Oroville, and Quincy, respectively. Plumas was established as the Plumas Forest Reserve by the General Land Office on March 27, 1905. In 1906 the forest was transferred to the U.S. Forest Service, and on March 4, 1907 it became a National Forest. On July 1, 1908 a portion of Diamond Mountain National Forest was added. The Bucks Lake Wilderness was officially designated in 1984 as a part of the National Wilderness Preservation System. A 2002 study by the Forest Service identified of the forest as old growth, using an economic type definition. The most common old-growth forest types are mixed conifer forests of:  Virtually no virgin timberland exists, as the area has been a logging epicenter starting with the gold rush continuing into the modern era.