North Fork John Day Wilderness

North Fork John Day Wilderness
IUCN category Ib (wilderness area)
A lake in the wilderness
Location	Grant / Umatilla counties, Oregon, United States
Nearest city	Granite, Oregon
Coordinates	44°55′01″N 118°35′03″W / 44.91694°N 118.58417°W / 44.91694; -118.58417Coordinates: 44°55′01″N 118°35′03″W / 44.91694°N 118.58417°W / 44.91694; -118.58417
Area	121,352 acres (49,109 ha)
Established	1984
Governing body	United States Forest Service

The North Fork John Day Wilderness is a wilderness area within the Umatilla and Wallowa–Whitman National Forests in the Blue Mountains of northeastern Oregon.

The wilderness consists of four separate units: the main 85,000-acre (34,000 ha) unit of the North Fork John Day drainage; the Greenhorn Unit to the south; the Tower Mountain Unit to the north; and the Baldy Creek Unit to the east. Approximately 6,000 acres (2,400 ha) of the Vinegar Hill-Indian Rock Scenic Area also lie within the wilderness.

The North Fork John Day Wilderness is located within the larger Elkhorn Fire Management Area, and the area's fire plan allows for the use of Prescribed Natural Fire under certain circumstances.

The North Fork John Day Wilderness is composed of rolling benchlands, steep ridges, alpine lake basins, and the granite outcrops of the Greenhorn Mountains at an elevation of 8,100 feet (2,500 m). It encompasses two entire subranges of the Blue Mountains—the Greenhorn Mountains and the ragged Elkhorn Mountains. A continuous vegetative canopy covers most of the land, including dense virgin stands of conifer species like Douglas-fir, white fir, western larch and lodgepole pine. The headwaters of several waterways are located in the wilderness, including Bull Creek, Baldy Creek, and Crawfish Creek, as well as the North Fork John Day River, 39 miles (63 km) of which are designated Wild and Scenic.

The granite and sedimentary rock that makes up much of the North Fork John Day Wilderness reflect the Blue Mountains' history as a volcanic island archipelago in the Pacific Ocean some 250 million years ago. As the crust of the earth shifted, the archipelago collided with the advancing North American Plate approximately 200 million years ago. Later, bubbles of less dense granitic rock, or batholiths, rose through the sediment to form the granite cores of the Elkhorn and Greenhorn ranges. Columbia River basalt flows buried the region some 15 million years ago, the remains of which can be seen today in the rimrock on the benchlands in the western portion of the wilderness.