In 1933, Aldo Leopold also published an essay entitled "The Conservation Ethic," which gives some notion of where his own gropings were leading. In it he continued to speak of "controlled wild culture or 'management,'" of cropping, and of "industrial forestry." But he also criticized the attitude that land is merely property, to be used in whatever way its owner liked. "The land-relation," he complained, "is still strictly economic, entailing privileges, but not obligations." One of the essay's subheadings read "Ecology and Economics." Already he had begun to think of the two as not altogether compatible; he was moving away from the view of conservation as resource supply-and- demand toward an attempt "to harmonize our machine civilization with the land whence comes its sustenance"—toward "a universal symbiosis."

According to Leopold's biographer, Susan Flader, this conversion to an ecological basis did not become complete until 1935, when he joined with others to form the Wilderness Society. It was also in that year that he saw firsthand the intensely artificial German methods of management, which he disliked so much that he grew wary even of his own inclination toward regulated landscapes. And during that watershed year, too, he found an old, abandoned shack near Baraboo, Wisconsin, where until his death he would at odd moments live the life of a Gilbert White or Henry Thoreau—a rural naturalist living apart from a technological culture, seeking to intensify his attachment to the earth and its processes. Henceforth Leopold's chief concern was the need to reestablish a personal, coexisting relation with nature, rather than the large-scale, impersonal management of resources by a professional elite.