Soil, Economics and Health

The following appeared in the Winter 2015 Winter Leopold Letter.... It is an excellent discussion of the function and importance of understanding the microbial content of our soils - and by extension, the beneficial role of bacteria, fungi and other microbes in the health of both soil and man. All the references are given at the end of the letter. If you are unfamiliar with the work and importance of Sir Albert Howard, read his biography on Wikipedia and read his book, Soil Health. It is available from on-line merchants.,




By Fred Kirschenmann, Leopold Center Distinguished Fellow

All natural resources, except only subterranean minerals, are soil or derivatives of soil. Farms, ranges, crops and livestock, forests, irrigation water, and even water power resolve themselves into questions of soil. Soil is therefore the basic natural resource.
It follows that the destruction of soil is the most fundamental kind of economic loss the human race can suffer.  With enough time and money, a neglected farm can be put back on its feet­—if the soil is still there. With enough patience and scientific knowledge, an overgrazed range can be restored—if the soil is still there.  By expensive replanting and with a generation or two of waiting, a ruined forest can again be made productive—if the soil is still there. With infinitely expensive works, a ruined watershed may again fill our ditches or turn our mills—if the soil is still there.  But if the soil is gone, the loss is absolute and irrevocable.  (Emphasis mine)               - Aldo Leopold
As 2015, the International Year of Soils, comes to a close, numerous organizations, including the Soil Science Society of America, have responded to this declaration by putting more emphasis on soil health than has ever been part of our international conversations. Still, we have much more to do.
Aldo Leopold already understood, almost a hundred years ago, that soil is, in many respects, a non-renewable resource. Once soil is “gone” its loss is “absolute and irrevocable.”  He also understood that such soil destruction is “the most fundamental kind of economic loss which the human race can suffer.”  We now also know from the report of Rick Cruse’s research, highlighted in the Fall 2015 Leopold Letter, that such economic loss is being reconfirmed in Iowa today!  The “average loss of 6.8 inches of topsoil due to erosion in Iowa since 1850, now causes an average of 10 bushels per acre yield loss.”
There are other initiatives taking place with regard to soil that are more hopeful and that deserve our attention now and in the decades ahead. First, Cornell University has produced a manual which clearly demonstrates that soil health is a scientifically verifiable phenomenon, and therefore enables us to learn how to manage and measure soil health.
Second, researchers are paying much more attention to the microbiome as it relates to both soil health and human health. In this regard, a new book by David Montgomery and Anne Bikle, The Hidden Half of Nature, is exceptionally inspiring. They focused on restoring the soil health in their own Seattle, Wash., garden, where the soil had been seriously degraded and depleted. Montgomery, a professional geologist, and Bikle, a biologist, environmentalist and health professional, learned that the key to restoring soil health lay in a part of nature that we have largely ignored—the microbial life in the soil as well as in ourselves. They awaken us to this “hidden half of nature” from science and experience, which comprises “the microbial roots of life and health” in soil and in us. In the process they make an important contribution to insights that Sir Albert Howard discovered on his own research farm in India, which led him to believe that the “N-P-K mentality” (or our modern input-dependent commodity agriculture) was headed in the wrong direction and that ultimately healthy soil, healthy plants, healthy animals, and healthy humans were all “one subject.”  Howard realized that his “boldly revised point of view” needed to be “fully researched with entirely fresh investigations,” which we have largely failed to do.
However, Montgomery and Bikle, along with many other researchers they mention in their book, point out that perhaps even Leopold was too pessimistic, since if we truly honor Howard’s “law of return” and allow microbial life in the hidden half of nature to perform its life restoring work, soil health can be restored in a relatively short period of time!
Third, there are health care professionals who are realizing that our current health care system, which focuses on dealing with sickness and very little on how to keep people healthy, is also the wrong direction. In her book Farmacology, Daphne Miller, a family medicine practitioner and professor, reveals that she learned how to be a more effective health care professional from Integrated Pest Management (IPM) farmers. Instead of putting all of their resources into getting rid of pests after they emerged, IPM farmers learned how to manage their farms to prevent pests from emerging in the first place. Dr. Miller realized that managing health care in ways that keep people healthy, rather than waiting until they get sick, was similarly important. And she discovered just how much healthy soil “influenced the day-to-day health” of her patients.
At the end of their book, Montgomery and Bikle make an interesting observation that could inspire us to take on new challenges as we begin to take the microbiome more seriously in both agriculture and health care: “So where does this revolutionary new perspective leave us?  Put bluntly, many practices at the heart of modern agriculture and medicine—two arenas of applied science critical to human health and well-being—are simply on the wrong path. We need to learn how to work with rather than against the microbial communities that underpin the health of plants and people.” (p. 255)


Aldo Leopold, “Erosion and Prosperity” ms. 1921, Included in The Essential Aldo Leopold Quotations and Commentaries, Edited by Curt Meine & Richard Knight.  (pp. 76-77)
B.K. Gugino, et. al. 2009, “Cornell Soil Health Assessment Training Manual”  (Second Edition)  A third edition will become available shortly.
David R. Montgomery and Anne Bikle, 2015. The Hidden Half of Nature; The Microbial Roots of Life and Health. New York: W.W. Norton & Company.
Sir Albert Howard, 1947. The Soil and Health.  Lexington:  The University of Kentucky Press (2006 edition)
Daphne Miller, 2013.  Farmacology: What Innovative Family Farming Can Teach us About Health and Healing. New York:  Harper Collins.
Daphne Miller, 2013.  “The Surprising Healing Qualities...of Dirt,”  YES Magazine

Back to Leopold Letter Winter 2015

- See more at: http://www.leopold.iastate.edu/news/leopold-letter/2015/winter/kirschenmann-rethinking-soil-economics-and-health#sthash.6gRbnBZl.dpuf


6 Delicious Edibles You Can Grow Indoors All Winter


Most homes are heated to a comfortably warm temperature range of 65 to 75F during winter. This is ideal for growing many vegetables, so the winter cold is not as much of an issue here as low-light conditions. Your choice would be limited unless you provide sufficient grow lights to imitate the sunny outdoors.

    As a general rule, leafy vegetables can manage with much less light than root vegetables. Fruiting vegetables such as tomatoes and eggplants need more light to ensure a good yield.


Watch video now