They called him the Rocky Mountain Greyhound, a sobriquet Bob Marshall earned from his U.S. Forest Service colleagues who clocked his rapid hikes through high-country wilderness. Marshall had mastered the quick-tempo pace on youthful sprints up Adirondack peaks, all the while metic-ulously recording altitude climbed and time expended; in August of 1920, he and his companions, with full backpacks, raced up and down 2000-foot-high Mount Basin in sixty-three minutes. The steeper Rockies offered greater challenges but did not slow his gait, even while shouldering seventy pounds of equipment.

Indefatigable, Marshall lived at full throttle. Trained as a forester, he noted shifts in terrain, ecosystem and habitat during his treks. As a wilderness enthusiast, he was captivated by the untrammeled. Like John Muir before him, he believed mountaineering was a tonic for urban jitters. “People cannot live generation after generation in the city,” Marshall asserted, “without serious retrogression, physical, moral and mental.”

Marshall initially joined the Forest Service in 1925 and worked for the next three years at the Northern Rocky Mountain Forest Experiment Station in Montana. He sided with Aldo Leopold and Arthur Carhart when they proposed that the Forest Service set aside inviolable pristine lands, and together they rebutted those foresters dismissive of “elitist” wilderness advocates. Democracy was meaningless if it did not protect minority prerogatives, including those for the few “who have an overwhelming longing to retire periodically from the encompassing clutch of mechanistic civilization. To them the enjoyment of solitude, complete independence and the beauty of undefiled panoramas is absolutely essential to happiness.” Putting words into action, Marshall, Leopold and others established the Wilderness Society in 1935, an enduring testament to their collective faith in nature as a preserve of liberty.

Marshall also allied himself with those battling industrial forestry. Although he was no longer in the Forest Service, after a 1930 meeting with foresters George Ahern, Ward Shepard and Raphael Zon at Gifford Pinchot’s home, he helped draft a scathing “Letter to Foresters,” published in the Journal of Forestry. It accused the profession of acquiescing to “woodland devastation,” a mark of its deepening “spiritual decay.”

The resultant furor clarified Marshall’s perspectives, and, just before becoming head of the Bureau of Indian Affairs’ Division of Forestry and Grazing, he fleshed them out in The People’s Forests, published in 1933. The book advanced a stiff defense of federal ownership of national forests predicated on past exploitation of public lands. “All through the nineteenth century and the first decade of the twentieth century,” Marshall declared, “the timber owners had taken a public-be-damned attitude toward the occasional proclamations of far-sighted idealists that private management of the forests was bringing havoc to public welfare.” Because “they held the whip hand, [and] controlled the legislative bodies in the most important lumber states,” they could pursue without check “a policy of devastation” in the woods from east coast to west.

Conservationists such as President Theodore Roosevelt and Pinchot had slowed these depredations by creating the Forest Service and the national forests under its care, but these Progressive Era reforms were being undercut, Marshall asserted, as contemporary foresters bowed before private enterprise’s demands for public subsidies. This “cooperative” relationship stymied much-needed criticism of the industry’s destructive practices, impelling Marshall to demand intensified regulation of lumber companies.

Increased oversight alone would not regenerate logged-over landscapes or rehabilitate the unemployed, so Marshall pressed a more radical agenda: the nationalization of all forest lands in the United States. With governmental ownership, the central object of management shifted from “private gain” to “social welfare,” a benefit that would be cheap at the cost. Marshall estimated that the price tag for purchasing an estimated 240 million acres of unproductive or abandoned lands would be a billion dollars, considerably less than the amount Congress appropriated annually for river and harbor improvements. The economic stimulation produced by employing thousands of laborers to repair the land and construct cabins and trails would be priceless, a conservationist agenda that would energize a battered body politic.

An enthusiastic socialist, Marshall recognized central government’s limitations but would not compromise on the national forests’ democratic promise. In 1934, he put this faith to work when he was promoted to director of the Indian Forest Service in the Department of the Interior, developing a plan whereby reservations would regain control of their natural resources and, through conservative management, would reclaim their sovereignty. Five years later he returned to the Forest Service to head the new division of Recreation and Lands, intending to extend protection to primeval landscapes throughout the national forest system, but he didn’t have the chance. That very year, Marshall died at age 38.

“I did not feel I knew him until after several thirty-mile walks in the wilderness,” a mournful John Sieker wrote, because it was on those energetic treks that a voluble Marshall “talked about his theories of life, and philosophies.” As they sped past majestic vistas, Sieker was swept up by Marshall’s idealistic convictions and galvanizing appeal; with his death, “the Forest Service has lost a conservationist who was willing and able to fight for the principles of true conservation to the end.”