Walking the Talk: Aldo Leopold


“One of the penalties of an ecological education is that one lives alone in a world of wounds” (Aldo Leopold, 1966:197).


“Of what avail are forty freedoms without a blank spot on the map?” Aldo Leopold (1966:158).


During the first decade of the 20th century, one American distinguished himself among most in his concern for wildlife management and conservation, Aldo Leopold (1887-1948), who was born in Burlington, Iowa. In 1909, Leopold graduated with a master’s degree from the Forestry School at Yale University. Next he joined the U.S. Forest Service to work in the district of Arizona and New Mexico. In 1933, he became the first professor of game management in the United States upon joining the faculty of the Agricultural Economics Department at the University of Wisconsin. Throughout the remainder of his life, Leopold concentrated on teaching, research, writing, and contributing to the development of environmental conservation policy (Callicott 2001:174). He was founder of the North American Wilderness Movement and helped to establish the Wilderness Society in 1935 (Callicott 2001:175). Leopold had and continues to have special gravitas because of his extensive professional experience as a field scientist (Meine 2008).

Leopold was a pioneer in numerous endeavors including game management (later termed wildlife ecology and management, and then conservation biology), wilderness preservation, ecological restoration (now restoration ecology), management of forests as ecosystems (now sustainable forestry), range management, soil erosion control, sustainable agriculture, back to the land movement and organic farming, environmental policy and law, community-based conservation, environmental history and historical ecology, environmental education, environmental ethics, outdoor recreation, and nature writing (Callicott 2001:176-179, Meine 2008).

From 1909 to 1924 Leopold conducted fieldwork in Arizona and New Mexico for the Forest Service. Among other initiatives, he developed the first comprehensive management plan for the Grand Canyon, wrote the Forest Service’s first game and fish handbook, and proposed the Gila Wilderness Area, the first national wilderness area in the Forest Service system. Meine (2008) remarks that: “Leopold earned a reputation within the Forest Service as one of its most able and creative leaders, highly regarded for his innovations in forest administration…. A decade later, in 1935, he helped to found the Wilderness Society, providing a broad philosophical and professional base for the new organization. Leopold also conducted important field research in forest ecology during his Forest Service years and, in 1924, was appointed assistant director of the Forest Products Laboratory in Madison, Wisconsin. He remained in that position for four years.”

Leopold championed the scientific management of wildlife habitats by private as well as public landholders in addition to government implemented game refuges, hunting laws, and other methods to protect specific species of preferred game animals. He viewed wildlife management as a technique for restoration ecology and for maintaining the diversity of animals and plants in an area, not simply for producing an abundance of game for hunting. His essay “Thinking Like A Mountain” exposes the serious ecological consequences when a top carnivore like wolves are removed from an ecosystem, what today would be called the trophic cascade with ramifications throughout the food web and biotic community.

Leopold’s interests were personal as well as scientific and academic. For instance, one way in which he pursued restoration ecology was through the 80-acre farm that he purchased in 1935 in Sauk County (in sand country) north of Madison in central Wisconsin. The previously forested land had been left barren and worn out after logging, overgrazing with dairy cows, and repeated fires. Named “The Shack” this farm is where he experimented with his ideas about land health and restoration ecology, working to conserve and build the soil as well as develop wildlife habitat. There he planted thousands of pine trees, wild flowers, prairie grasses, and other plants, and observed the changes in the ecology of the landscape over time. Leopold also worked on restoration ecology at the arboretum and other lands of the University of Wisconsin (Meine 2008).

It is also at The Shack where Leopold wrote his most famous book, A Sand County Almanac, a collection of essays about his experiences, observations, and thinking regarding the place of humans in nature. But only one week after he heard about its acceptance for publication he died of a heat attack while fighting a neighbor’s wildfire that threatened his shack and land. Already by the mid-1960s some 20,000 copies of the book were sold (Meine 2008). It quickly became recognized as a classic in nature writing and by now has sold well over two million copies. It has been translated into 10 languages (Barakatt 2008). As Meine (2008) says: “A Sand County Almanac helped to stimulate environmental literacy among the American public; conversely, readership of A Sand County Almanac and recognition of Leopold’s contributions grew along with that increasing awareness.” To this day it is regularly assigned as reading in numerous university and college courses on ecology, environmentalism, conservation, and related subjects like historical ecology. Scholars continue to analyze this book and his many other technical and popular publications as well as the Aldo Leopold Archives at the University of Wisconsin for new insights through intellectual biographies and other venues (e.g., Callicott 1987, 1989, 1999, Newton 2006).

The Shack was also a beloved weekend and holiday retreat for Leopold’s entire family. His five children all became natural scientists and environmentalists, most of them university professors (Barakatt 1969). This is another most important way in which his legacy has continued. (See Barakatt 2008 on “Aldo Leopold’s Children”).

As Leopold’s daughter, Nina Leopold Bradley (2008) observes: “Aldo Leopold’s land ethic expresses a moral theory that begins, literally and philosophically, with what we know best – firsthand experience. Through his own participation in the land community, he came to a deeper understanding and appreciation of the land community. On his Wisconsin sand county farm, the Shack, he struggled to rebuild a diverse, healthy and aesthetically satisfying biota on his own abused land. Here again, Leopold experienced a profound humility as he became acutely aware of the complexity of factors involved in life and death, growth and decay. Ethical and aesthetic values guided his decisions.”

From his own childhood Leopold developed an ethical and aesthetic sensibility. Following his father as his childhood role model, Leopold was an enthusiastic hunter, fisher, sportsman, and outdoorsman. Even before the establishment of game laws his father imposed a hunting ethic on himself and his three sons that involved a closed season and bag limits. Leopold dedicated his first book, Game Management, to his father. It became the standard textbook on the subject for decades. As Meine (2008) observes: “He guided the field through its first important decade, leading it beyond its original mission of perpetuating populations of game animals and integrating it with other conservation fields. In the process, he provided foundations for later developments in ecology, sustainable agriculture and conservation biology.” Meine (2008) also notes that: “Securing wildlife conservation’s foothold in academe would be one of Leopold’s premier accomplishments in the remaining 15 years of his life.”

Aldo’s mother was fond of music and opera in particular. She instilled in Aldo a keen appreciation of the aesthetic (Callicott 2001:174). From his childhood onward he was a keen observer of nature keeping records and making sketches. Although a life-long hunter, eventually he turned more toward wildlife research, mirroring his shift from an emphasis on wilderness for recreation to its conservation. He believed that wilderness was important for the preservation of threatened species and to provide a baseline for the assessment of land health, the latter now referred to as ecosystem health with normal ecosystem functions and processes. Land health referred to the capacity of the land for self-renewal of the biotic community (Callicott 2001:175-176).

Although Leopold had been passionately engaged in the intimate exploration and observation of nature since his childhood, a profound inner change in his attitude and values toward wildlife was influenced by an epiphany which he describes as part of his involvement in the extirpation of wolves in the southwest:

“We reached the old wolf in time to watch a fierce green fire dying in her eyes. I realized then, and have known ever since, that there was something new to me in those eyes—something known only to her and to the mountain. I was young then, and full of trigger-itch; I thought that because fewer wolves meant more deer, that no wolves would mean hunters’ paradise. But after seeing the green fire die, I sensed that neither the wolf nor the mountain agreed with such a view” (Leopold 1966:138-139).

A trip to the Sierra Madre Occidental in Mexico also contributed to changes and developments in his view of nature and the place of humans in it (Newton 2006).

This transformation, perhaps even a spiritual one, is reflected in Leopold’s writings including his essays “Escudilla” and “Song of the Gavilian” as well as in “Thinking Like a Mountain” in which he relates the experience with the dying wolf (Meine 2008).

“The Land Ethic” is the final essay in Leopold’s classic book A Sand County Almanac. It is grounded in the evolution of Charles Darwin and the ecology of Charles Elton, in particular the concept of the biotic community from Elton. Leopold viewed the individual organism as part of a community of interdependent parts and therefore cooperation was pivotal. His ethics extends the boundaries of the community to include the land which encompasses the waters, soils, plants, and animals. The role of humans becomes as a good citizen of the community rather than subjecting the latter to conquest and exploitation (Callicott 2001:179). Thus, he succinctly states the land ethic as: “A thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. It is wrong when it tends otherwise” (Leopold 1949:224-225). (Today, the concept of stability would be replaced by resilience).  As Bradley notes:

“Throughout Aldo Leopold’s life, he persisted in his personal, intellectual struggle to understand better the land community and his own participation in it. Recording and integrating all of the strands of his own firsthand experience, he came to his final statement of the land ethic, a product of the heart as much as of the mind. With his use of the words “loved” and “respected,” we can see already that he was integrating his factual science with a much broader humanism.”

She quotes him: “That land is a community is the basic concept of ecology, but that land it to be loved and respected is an extension of ethics.” She also writes that: “During the course of Leopold’s life, he worked to blend his ecological science with philosophy and even biblical history.” She mentions that: “In my father’s essays, we hear an emotional thread of consilience. He brought together nature and culture, emotion and intellect, philosophy and science, ethics and aesthetics” (Bradley 2008). (See Wilson   ).

Accordingly, Leopold rejected the utilitarian, wise land use, or sustainable resource use approach to environmental conservation of contemporaries like Gifford Pinchot and Theodore Roosevelt in favor of a more preservationist and ecocentric approach based on his land ethic and related concepts like land health. Following the lead of Charles Elton and others in the new science of ecology, Leopold applied concepts like ecosystem and biotic community as they developed. He rethought his view of predator eradication turning to the idea of a balance between predator and prey, such as wolves and deer in the mountains of the southwest.

Leopold was critical of dominant orientations in American frontier culture of individualism, get-rich-quick mentality, and the commodification of nature as contrary to ecological reality, conscience, and ethics (Newton 2006:14-15). Instead he prescribed an intelligent humility regarding the place of humans in nature. At the same time solution to environmental concerns was to be found not only in science, government, and similar social institutions, but more fundamentally in changes in individual thought and action, something that he exemplified (Meine 2008).

Leopold wrote that: “Conservation is a state of harmony between men and land.” Guidelines for conservation guidelines amounted to: “obey the law, vote right, join some organizations and practice what conservation is profitable on your own land; the government will do the rest.” (Leopold 1949:243-244). “The land ethic simply enlarges the boundaries of the community to include soils, waters, plants, and animals, or collectively: the land.” “This sounds simple: do we not already sing our love for and obligation to the land of the free and the home of the brave? Yes, but just what and whom do we love? Certainly not the soil, which we are sending helter-skelter down river. Certainly not the waters, which we assume have no function except to turn turbines, float barges, and carry off sewage. Certainly not the plants, of which we exterminate whole communities without batting an eye. Certainly not the animals, of which we have already extirpated many of the largest and most beautiful species. A land ethic of course cannot prevent the alteration, management, and use of these‘resources,’ but it does affirm their right to continued existence, and, at least in spots, their continued existence in a natural state. In short, a land ethic changes the role of Homo sapiens from conqueror of the land-community to plain member and citizen of it. It implies respect for his fellow-members, and also respect for the community as such.”  (For more on land ethic see:  Aldo Leopold’s Land Ethic http://www.eoearth.org/article/Aldo_Leopold’s_Land_Ethic).

Leopold did not exactly follow either Gifford Pinchot’s resource conservation (wise-use) or John Muir’s wilderness preservation. Instead he pursued what J. Baird Callicott (2008) calls a human-harmony-with-land paradigm of conservation in connection with the concept of land health. Callicott (2008) writes that: “Once again, he anticipated by half a century recent development in conservation philosophy.  For only in this decade has the “new” concept of ecosystem health become broadly current. There is a new International Society for Ecosystem Health, a journal named Ecosystem Health and several international congresses on ecosystem health were convened in the 1990s. As now more fully developed, land or ecosystem health refers to the functionality of ecosystem processes. It is different from and complementary to another concept with which it is often conflated, biological integrity. A biotic community has integrity if all of its native species are present in their characteristic numbers interacting in their natural ways. An ecosystem is healthy if it produces biomass, recruits, retains, and cycles nutrients, holds the soil, modulates water flow, and maintains other ecosystem processes—whether these processes are carried out by native or exotic, or wild or domestic species.”

Some of the elements of Leopold’s thinking, such as his emphasis on affection and aesthetics in human relations with nature are antecedents in the development of the deep ecology pioneered by Norwegian philosopher Arne Naess. Also, Leopold asserted that “no important change in ethics was ever accomplished without an internal change in our intellectual emphasis, loyalties, affections and convictions” (Harding 2006:65). This reflects not only Leopold’s insightful integration of approaches from the natural sciences and humanities, but also subsequent thinking by many in spiritual ecology.

Although the breadth of Leopold’s work was far wider, he is best known by many for developing one of the earliest, and probably the most famous, statements of environmental ethics, one that developed into the whole field of environmental philosophy and ethics, and one that is at the foundation of spiritual ecology. As environmental philosopher and ethicist J. Baird Callicott (2001:179) notes: “… the very idea of a land or environmental ethic, and Leopold’s sketch of its contours, has taken the contemporary environmental movement out of the domain of mere utility and into that of morality. If for no other reason, then for this one, Leopold would deserve the frequently conferred metonym of `prophet’ and his masterpiece that of `the bible of the contemporary environmental movement’.”  Accordingly, it is most appropriate to include some excerpts from and comments on “The Land Ethic” essay in his book A Sand County Almanac (Leopold 1966).



“An ethic, ecologically, is a limitation on freedom of action in the struggle

for existence. An ethic, philosophically, is a differentiation of social from anti-social conduct. These are two definitions of one thing” (p. 238).

“All ethics so far evolved rest upon a single premise: that the individual is a member of a community of interdependent parts…. The land ethic simply enlarges the boundaries of the community to include soils, waters, plants, and animals, or collectively: the land” (p. 239).

“A land ethic of course cannot prevent the alteration, management, and use of these `resources,’ but it does affirm their right to continued existence, and, at least in spots, their continued existence in a natural state” (p. 240).

Also, he mentions the right of organisms elsewhere (p. 247).

“No important change in ethics was ever accomplished without an internal change in our intellectual emphasis, loyalties, affections, and convictions. The proof that conservation has not yet touched these foundations of conduct lies in the fact that philosophy and religion have not yet heard of it” (p. 246).

“An ethic to supplement and guide the economic relation to land presupposes the existence of some mental image of land as a biotic mechanism. We can be ethical only in relation to something we can see, feel, understand, love, or otherwise have faith in” (p. 251).

“A land, ethic, then, reflects the existence of an ecological conscience, and this in turn reflects a conviction of individual responsibility for the health of the land. Health is the capacity of the land for self-renewal. Conservation is our effort to understand and preserve this capacity” (p. 258).

Also, Leopold refers to the “A-B Cleavage” in conservation, the camp that views environment as a store of natural resources, and the other that views it as something more akin to what would now be called ecosystem (pp. 258-259).

“It is inconceivable to me that an ethical relation to land can exist without love, respect, and admiration for land, and a high regard for its value. By value, I of course mean something far broader than mere economic value; I mean value in the philosophical sense” (p. 261).

Leopold asserts that land-use must be assessed in terms of what is ethically and esthetically right instead of only economic expedience (p. 262).

“The bulk of all land relations hinges on investments of time, forethought, skill, and faith rather than on investments of cash. As a land-user thinketh, so he is” (p. 263).

“The evolution of a land ethic is an intellectual as well as emotional process” (p. 263).

Finally, Leopold recognizes multiple uses of wilderness for recreation, science, and wildlife itself (pp. 264-279). He writes: “Wilderness areas are first of all a series of sanctuaries for the primitive arts of wilderness travel, especially canoeing and packing” (p. 270).




Leopold shares with Henry David Thoreau, Rachel Carson, and others an environmental virtue ethics, according to philosopher Philip Cafaro (2001:13-16). It includes the following principles: “A desire to put economic life in its proper place – that is, as a support for comfortable and decent human lives, rather than as an engine powering endlessly more acquisition and consumption…. A commitment to science, combined with an appreciation of its limits…. Nonanthropocentrism [extending moral considerability to the nonhuman world]…. An appreciation of the wild and support for wilderness protection.”

Over the decades during his life Leopold exerted tremendous influence within the United States and beyond. As Meine (2008) notes: “He was a widely respected communicator, constantly writing and speaking to varied audiences on a wide range of conservation topics. As a teacher, he instructed leading professional as well as hundreds of undergraduate students at the University of Wisconsin. He participated actively in dozens of professional societies and conservation organizations at the local, state, national and even international levels, and was a prominent player in the development of conservation policy throughout his career.”  Fuerthermore, Meine (2008) writes: “During his lifetime, Leopold’s reputation reflected many qualities: his facility with words, the effectiveness of his teaching, the breadth of his conservation philosophy and especially the degree to which he matched word and thought with deed.”

Leopold’s legacy, and most of all his Sand County Alamanc, is still being discovered and reconsidered by professionals and the public from diverse arenas of interest as it links generations of environmental professionals and activists. In particular, as Curtis Mein, a major biographer of Leopold affirms: “Leopold defined challenges that remain at the core of conservation thought and practice more than a half-century after his death, even as conservation concerns increasingly overlap other issues in contemporary life.” This is reflected in number organizations and initiatives such as the Aldo Leopold Memorial Award, Aldo Leopold Legacy Trail System, Aldo Leopold Wilderness, Leopold Center for Sustainable Agriculture, Leopold Education Project, Leopold Heritage Group, Aldo Leopold Leadership Program, Aldo Leopold Nature Center, Aldo Leopold Wilderness Research Institute, Sand County Foundation, and Leopold Conservation Award.

Meine (2008) identifies some of the forces that may have contributed to the continuing relevance of Leopold to this day, a rather different era of history in some respects if not in others. One is the need for a more holistic and interdisciplinary approach to ongoing environmental degradation that is informed by ethics. Here of particular relevance for spiritual ecology is Meine’s (2008) observation that: “Leopold regarded the lack of attention from philosophy and religion as “proof that conservation [had] not yet touched [the] foundations of conduct”; the consolidation of environmental ethics and the greening of religion now may be regarded as proof that it has at last begun to touch those foundations.” Indeed, since the early 1950s many in reflecting on Leopold have referred to him as the priest or prophet of the environmental movement and his book A Sand County Almanac as its bible or scripture (Meine 2008, e.g., Nash 2001:182-199). For many, the reference is more than merely metaphorical.

Deep ecologists and so-called radical environmentalists in organizations like Earth First! have also been inspired by Leopold as well. Meine (2008) writes that:  “Leopold’s powerful image of the faltering “green fire” in the eyes of the dying wolf of “Thinking Like a Mountain” came to symbolize for this new generation of wilderness activists the loss of the North American wilds. “A militant minority of wilderness-minded citizens,” they read in Leopold’s essay “Wilderness,” “must be on watch throughout the nation and available for action in a pinch.” At the same time, their philosophical standard-bearers in the deep ecology movement could point to “The Land Ethic” as a foundational document.” Meine (2008) goes on to say that: “As the environmental professional class grew, however, the grassroots activists, driven by powerful social, political and spiritual motives, hardly went away. The result, in a sense, was a splitting of the Leopold legacy. Suited professionals could see Leopold as a sort of master diplomat and spokesman, able to speak to all sides on environmental issues. Activists could see Leopold as a committed and deeply honest radical, who message provided intellectual armor.”

There are continuities as well as discontinuities in the intellectual genealogy of nature conservation and more broadly environmentalism, and the former are not always easy to demonstrate without exhaustive archival as well as library research. The situation is analogous to the complexities of the intertwined food web in ecosystems, only the flow of nutrients is in the form of ideas. But available information is more than suggestive if not always conclusive of the historical influences in successive decades. In various ways to some degree there is an intellectual genealogy from Thoreau to Muir to Leopold, although many other contributing factors are involved to complicate the history.


The Encyclopedia of Earth has several articles on Leopold. See http://www.eoearth.org.  The Journal for the Study of Religion, Nature, and Culture devoted a special issue to Leopold in December 2011 (v. 5, no. 4). [Also see original notes in SEbkLeopold].



Aldo Leopold Archives, University of Wisconsin, Madison http://digicoll.library.wisc.edu/AldoLeopold.

 Aldo Leopold Foundation, Baraboo, Wisconsin http://www.aldoleopold.org.

Aldo Leopold Foundation, 2010, “Aldo Leopold’s Legacy,” Aldo Leopold Collection and the Encyclopedia of Earth http://www.eoearth.org/article/Aldo_Leopold’s_Legacy.

Aldo Leopold’s Land Ethic http://www.eoearth.org/article/Aldo_Leopold’s_Land_Ethic.

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Botkin, D.B., 1990, Discordant Harmonies: A New Ecology for the Twenty- first Century, New York, NY: Oxford University Press.

Brown, David E. and Carmony, Neil B., eds., 1990, Aldo Leopold’s

Southwest, Albuquerque, NM: University of New Mexico Press.

Callicott, J. Baird, ed., 1987, Companion to A Sand County Almanac: Interpretive and Critical Essays, Madison, WI: University of Wisconsin Press.

_____ , 1989, In Defense of the Land Ethic: Essays in Environmental

Philosophy, Albany, NY: State University of New York Press.

_____,  1999, Beyond the Land Ethic: More Essays in Environmental

Philosophy, Albany, NY: State University of New York Press.

_____,  2001, “Aldo Leopold 1887-1948,” in Fifty Key Thinkers on the Environment, Joy A. Palmer, ed., New York, NY: Routledge, pp. 174-180.

_____, and Eric T. Freyfogle, eds., 1999, For the Health of the Land: Previously Unpublished Essays and Other Writings by Aldo Leopold, Washington, D.C.: Island Press.

Cafaro, Philip, 2001, “Thoreau, Leopold, and Carson: Toward an Environmental Virtue Ethics,” Environmental Ethics 22(1?):3-17

Errington, P.L. 1948 (October), “In Appreciation of Aldo Leopold,” The Journal of Wildlife Management 12(4):341-350. http://www.eoearth.org/article/Tributes_to_Aldo_Leopold

Flader, Susan L., 1974, Thinking Like a Mountain: Aldo Leopold and the Evolution of an Ecological Attitude Toward Deer, Wolves, and Forests, Columbia, Missouri: University of Missouri Press.

Flader, Susan L., and J. Baird Callicott, eds., 1991, The River of the Mother of God and Other Essays  by Aldo Leopold, Madison, WI: University of Wisconsin Press.

Flader, Susan with Charles Steinhacker, 1973, The Sand Country of Aldo Leopold, San Francisco, CA: Sierra Club Books.

Harding, Stephan, 2006, “Aldo Leopold: Noble Naturalist,” in Visionaries: The 20th Century’s 100 Most Important Inspirational Leaders, Satish Kumar and Freddie Whitefield, eds., White River Junction, VT: Chelsea Green Publishing, pp. 64-65.

Knight, Richard, and Suzanne Riedel, eds., 2002, Aldo Leopold and the Ecological Conscience, New York, NY: Oxford University Press.

Lannoo, Michael J., 2010, Leopold’s Shack and Ricketts’s Lab: The Emergence of Environmentalism, Berkeley, CA: University of California Press.

Leopold, Aldo, 1933, Game Management, New York, NY: Charles Scribner’s Sons.

_____, 1949, A Sand County Almanac and Sketches Here and There, New York, NY: Oxford University Press.

Leopold Center for Sustainable Agriculture http://www.leopold.iastate.edu

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_____, 2008, “The Secret Aldo Leopold, or Who Really Wrote A Sand County Almanac?,” in “Aldo Leopold’s Legacy,” Encyclopedia of Earth http://www.eoearth.org/article/Aldo_Leopold’s_Legacy (This essay was written by Curt Meine, Research Associate, International Crane Foundation, for presentation at a 1999 conference called “Aldo Leopold’s Land Ethic: A Legacy for Public Land Managers” at the U.S. Fish and Wildlife Service’s National Conservation Training Center in West Virginia. It was published originally in the Proceedings, Aldo Leopold’s Land Ethic: A Legacy for Public Land Managers. (Wadsworth, K., H. Kirchner, and J. J. Higgins, editors. 2000. Pheasants Forever, St. Paul, MN. 155 pp).

_____, and Knight, Richard L., eds., 1999, The Essential Aldo Leopold, Madison, WI: University of Wisconsin Press.

Nash, Roderick, 1967, Wilderness and the American Mind, New Haven, CT: Yale University Press.

Nash, Roderick, 2001, Wilderness and the American Mind, New Haven, CT: Yale University Press (Fourth Edition).

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