The Lost Forest Research Natural Area is a designated forest created by the Bureau of Land Management to protect an ancient stand of Ponderosa pine in the remote high desert county of northern Lake County, in the southeastern portion of Oregon. Lost Forest is an isolated area of pine trees separated from the nearest contiguous forest land by forty miles of arid desert. There are no springs or surface water in Lost Forest, and much of the southwest portion of the natural area is covered by large shifting sand dunes that are slowly encroaching on the forest.