Yosemite National Park The State of California, however, retained control of Yosemite Valley and Mariposa Grove. Muir also helped persuade local officials to virtually eliminate grazing from the Yosemite high country. The newly created national park came under the jurisdiction of the United States Army's Troop I of the 4th Cavalry on May 19, 1891, which set up camp in Wawona with Captain Abram Epperson Wood as acting superintendent. By the late 1890s, sheep grazing was no longer a problem, and the Army made many other improvements. The cavalry could not intervene to ease the worsening condition of Yosemite Valley and Mariposa Grove.
Yosemite National Park River Gorge. Lee Vining Glacier carved Lee Vining Canyon and emptied into Lake Russel (the much-enlarged ice age version of Mono Lake). Only the highest peaks, such as Mount Dana and Mount Conness, were not covered by glaciers. Retreating glaciers often left recessional moraines that impounded lakes such as the long Lake Yosemite (a shallow lake that periodically covered much of the floor of Yosemite Valley). With its scrubby sun-baked chaparral, stately groves of pine, fir, and sequoia, and expanses of alpine woodlands and meadows, Yosemite National Park preserves a Sierra Nevada landscape as it prevailed before Euro-American settlement. In