Jackson Lears has a long review essay at The New Republic discussing several new books on the history of American environmentalism. It's a mostly flattering overview, though Lears does spend some time on the ugly views of Progressive Era reformer and conservationist Madison Grant:
Grant was also a fervent Anglo-Saxon supremacist who popularized the scientific racism of his time in 1916 in The Passing of the Great Race—a compendium of conventional wisdom that sought to sound the alarm over swarming immigrants, rallying its WASP readers to greater fecundity. The book was widely praised (except in The New Republic, where the anthropologist Franz Boas pointed out the flimsiness of the category "race" and observed that Grant's maps were "entirely fanciful in their details"). [Theodore] Roosevelt sent Grant an admiring letter about the book, and F. Scott Fitzgerald put Grant's ideas in the mouth of Tom Buchanan in The Great Gatsby. Buchanan was just the sort of truculent, privileged airhead who would have been eager to display his intellect by citing middlebrow race science. The Passing of the Great Race captured the racial hysteria that bubbled barely beneath the surface of American popular culture in the 1910s and 1920s. And it made Madison Grant more famous for his race theory than for his conservation efforts….
In spotlighting the connection between wildlife management and eugenics, [historian Jonathan Peter] Spiro has put his finger on something important. The obsession with improving breeding stock linked Grant with Hitler on the right and with other more respectable eugenicists on the left, including Margaret Sanger (who promoted birth control) and Theodore Roosevelt (who hated it). Sanger wanted "to breed a race of human thoroughbreds," while Roosevelt warned Anglo-Saxons against "race suicide." Eugenics sanctified the marriage of racism and modernity. Throughout the 1910s and 1920s, the leaders of the American Eugenics Society dressed in white and paraded their obsessions with purity, organizing Fitter Families competitions, counterposing Nordics against the menace of Jews and other immigrants, not to mention the even greater menace of Negroes. When Grant argued that the health of the body politic required restricting the flow of foreigners to our shores, Roosevelt agreed. "The national gizzard cannot masticate more," he wrote. Grant's eugenic vision was ruling-class conventional wisdom, consistent with managing immigrants as well as managing wildlife.