The Challenge Experimental Forest occupies 1,446 ha at the western edge of the Feather River District of the Plumas National Forest. Site quality is rated high to very high. The predominant overstory is 100-140-year-old, even-aged Pacific ponderosa pine, but mixed conifer and mixed hardwoods types are also present. The Experimental Forest was formally designated in 1942 but not activated until 1958 when it was enlarged to its present boundaries. It was chartered to study and demonstrate silvicultural approaches to managing young-growth forests at lower elevations on the west slope of the Sierra Nevada. Activities peaked during the 1960's when a resident staff of 5 oversaw a series of regeneration cutting experiments. Subsequent research included the relationship of opening size to regeneration success and exploratory work in hardwood management. Currently active experiments center on understory fuel reduction, tree spacing and understory competition, and issues of sustainable productivity. Today the Forest is administered entirely out of Redding.