Located on the Jackson Demonstration State Forest near Fort Bragg, California, the North Fork (473 ha) and South Fork (424 ha) tributary watersheds of Caspar Creek (39° 21' N, 123° 45' W) serve as research sites for evaluating the effects of timber management on streamflow, sedimentation, and erosion. Established in 1961 as a cooperative effort between the California Department of Forestry and Fire Protection (CAL FIRE) and the United States Forest Service Pacific Southwest Research Station (PSW), the Caspar Creek study has evolved from a simple paired watershed study into one of the most comprehensive and detailed investigations of its kind. PSW and CAL FIRE have a 100-year Memorandum of Understanding to continue research at the site at least through 2099. Caspar Creek is one of 11 USFS Experimental Forests and Ranges selected in 2007 to complement the national network of Long Term Ecological Research sites.
The half-century-long record from the North and South Forks of Caspar Creek is unique in providing long-term hydrologic data from small, rain-dominated watersheds located in 2nd- and 3rd-growth conifer forests. Because of the kinds of research carried out, the lengthy record, and the relevance of site conditions to major water supply sources, the Caspar Creek Experimental Watersheds have long provided information used both to extend basic knowledge and to guide land management practices.