Sierra Nevada environmental history between 1820 and 1960 can be divided into three clear phases. The first period, 1820–1900, in- cluded entrance by European-Americans, displacement of Native Americans, the discovery of gold, and the development of other re- sources such as timber, water, rangeland, and scenic sites. Concern for the effects of this development led to the creation of Yosemite Valley as a state park and the designation of Sequoia and Yosemite (not including the valley) as national parks. Additional Sierra Nevada forestland was included in several federal forest reserves. No effec- tive system of regulation accompanied the creation of these areas, however. The second period of the Sierra Nevada's history, 1900– 1940, saw the creation of the U.S. Forest Service and the National Park Service and the beginning of effective management of Sierra Nevada resources by these agencies. Even as federal action was being taken, private development of natural resources continued, especially logging. Automobile access stimulated recreation demand. Decisions to provide Sierra Nevada water for San Francisco, Los Angeles, and numerous hydroelectric projects affected the range as well through this period. The third period of the range's environmen- tal history, 1940–60, was marked by accelerated use of all of its re- sources, especially timber and water. Improvements in automobile transportation led to increased winter uses associated with skiing. Federal and state agencies responded by trying to meet these grow- ing demands. By 1960, many environmental groups and some ele- ments within the federal services began to express concern over the effects of such accelerated growth. A period of environmental activ- ism in the Sierra Nevada was about to begin.
Beesley, David, "Reconstructing the landscape: an environmental history, 1820-1960" (1996). Aspen Bibliography. Paper 1804.