"The conservation of natural resources is the fundamental problem," Theodore Roosevelt said in 1907, "unless we solve that problem, it will avail us little to solve all others."
Even in 1907, conservation was an old idea -- 35 years earlier, in 1872, The world's first national park, Yellowstone, was created by Congress and signed into law by Ulysses S. Grant.
Yet outside of protected areas, the harvesting of natural resources persisted and—by the early 20th century—had intensified to an alarming degree.
Vast stretches of forest were clear cut. The state of New Hampshire, for example, lost more than 50 percent of its forest cover by the turn of the century and by 1920 more than 90 percent of primary forests in the United States had been cut.
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Photo credit: Library of Congress/Creative Commons