Gifford Pinchot promoted conservationism—the efficient management of natural resources by trained professionals. He was the first head of the U.S. Forest Service, appointed by President Theodore Roosevelt.
John Muir crusaded to stop the despoilment of natural places by western cattle and sheep ranchers and was instrumental in the creation of Yosemite and other national parks such as Grand Canyon, Petrified Forest, Mount Rainier, and Sequoia. His efforts culminated in the founding of the Sierra Club in 1892.
George Bird Grinnell (1849-1938) was raised in New York where his family lived for a time on the former estate of John James Audubon.
John Burroughs (1837-1921) was one of several naturalists whom Theodore Roosevelt knew because of his role in the evolving conservation movement of the early twentieth century.
The Boone and Crockett Club (1888-present) was the brainchild of Theodore Roosevelt and George Bird Grinnell, the editor of the influential magazine Forest and Stream.
The Antiquities Act of 1906 gave either the President or Congress authority to set aside historic landmarks and other objects of historic and scientific interest, protecting them from looting and destruction. President Roosevelt used the Act to designate many sites, including the Grand Canyon, as national monuments.