Headquartered in Washington, D.C., the United States Department of Agriculture Forest Service has a history of managing public lands. Established in 1905, the Forest Service has numerous regional offices that manage more than 150 national forests and grasslands. The districts construct and maintain trails, operate campgrounds, regulate grazing, patrol wilderness areas, and manage vegetation and wildlife habitat. The Forest Service also has regional research stations, including the International Institute of Tropical Forestry and Forest Products Laboratory. It also provides funding and technical assistance to nonfederal landowners through a branch called State and Private Forestry. The United States Department of Agriculture Forest Service maintains an office in Williams, Ariz.