The natural area's deep sandy soil has helped the Lost Forest ponderosa pines survive in the arid high desert environment. The Lost Forest soil was formed from lake sediments and alluvial materials. Pumice sands from Mount Mazama and Newberry Crater appear in the surface soils throughout the Lost Forest area. The post-Pleistocene lake environment formed the ash sediments from Mount Mazama into porous ground soil. The soils are underlain by hard calcium carbonate caliche layer several inches thick. This subsurface layer is impervious to water drainage and is seldom penetrated by roots. As a result, ground water is held near the surface. The local ponderosa pines make use the moisture held in the porous soil above the caliche barrier. In addition, scientists have found that the pine seeds from the Lost Forest trees germinated more quickly than other ponderosa pine seeds, suggesting a local adaptation to the arid environment is now a common characteristic of the Lost Forest ponderosa pine community.