Yosemite National Park a larger national park by 1890, one which encompassed the valley and its surrounding mountains and forests, paving the way for the National Park System. Yosemite is one of the largest and least fragmented habitat blocks in the Sierra Nevada, and the park supports a diversity of plants and animals. The park has an elevation range from and contains five major vegetation zones: chaparral and oak woodland, lower montane forest, upper montane forest, subalpine zone, and alpine. Of California's 7,000 plant species, about 50% occur in the Sierra Nevada and more than 20% are within Yosemite. The park contains suitable
Yosemite National Park U.S. Congress authorized the O'Shaughnessy Dam through passage of the Raker Act. In the late 1920s a bid for Yosemite for the 1932 Winter Olympics was put forward. Ultimately, the 1932 Winter Olympics were awarded to Lake Placid, New York. In 1937, conservationist Rosalie Edge, head of the Emergency Conservation Committee (ECC), successfully lobbied Congress to purchase about 8,000 acres of old-growth sugar pines on the perimeter of Yosemite National Park that were to be logged. More recently, preservationists persuaded Congress to designate , or about 89% of the park, as the Yosemite Wilderness—a highly protected wilderness area. The Park