Carl F. Jordan, Founder of Spring Valley Ecofarms

Bridging the gap between theoretical ecosystem science and practical management of farms, forests, and watersheds.

As a boy in the 1940s, I spent summers in Northern Maine and was dismayed by the destruction of the spruce fir forests by the pulp and paper companies.  I knew something was wrong, but I wasn’t sure what. I thought that by studying forestry I could figure it out, so in 1953, I enrolled in the forestry curriculum, School of Natural Resources, University of Michigan. It took me two years to figure out that forestry (as taught in the 1950s) was not the solution, it was the problem. I switched to the “Conservation” curriculum, and  was taught that “Conservation” meant “Wise Use.” It soon became clear that “Wise Use” could mean anything anybody wanted it to mean.”  Disillusioned, I joined the Navy and had the good fortune to be stationed in Monterey California, where I spent my free time in Point Lobos State Park, photographing how the interaction of wind, sea, and rocks formed the dramatic landscape.  About that time, Rachel Carson published “Silent Spring”, and I realized that Ecology might be the path toward less destructive resource management. That was in 1962, and few Universities offered programs in ecology.  I tried Rutgers University, where ecology was taught in the botany department. Again I was disappointed. The major research question was whether plants in nature grew in discrete communities or whether there was a gradient between what was called “forest types”. The question had no practical implications.  But I took a course in soil morphology in the agriculture college from Prof. John Tedrow.  He introduced me to the concept of nutrient cycling, and that led to my Ph.D. research on the movement of nutrients through the podzol soils of Southern New Jersey. Although the study was theoretical, I was inspired by the applied potential of the concept.

My first professional position was with H.T. Odum, in a study of radiation in the Puerto Rican rain forest.  My job was to trace Strontium 90 and Cesium 137 from atmospheric fallout through the forest.  Odum was overwhelming.  He was always talking about energy flow through the forest and how energy was driving the cycles of isotopes through the forest. It took a year for me to understand what he was talking about. In 1969, I moved my family to Argonne National Laboratory, where I collaborated with Dr. Don Sasscer, a nuclear physicist, in modeling the cycling data I had collected in Puerto Rico.  I was awarded the Ecological Society Mercer Prize for our paper on stability of isotope cycles in natural and managed ecosystems.

In 1974, I took the opportunity to join the Institute of Ecology at the University of Georgia, to participate in an international study of the rain forest in the Amazon Territory of Venezuela. We moved to Caracas, and I commuted by bush plane to the study site at San Carlos de Rio Negro, 800 miles to the South. I led a study of the cycle of nutrients in the rain forest, and the change in cycling due to shifting cultivation (sometimes called slash and burn).  In the control forest, we used radioisotope tracers to determine that 99.9  percent of the nutrients in leaf fall and rain fall were recycled from decaying organic matter on the soil surface back into the roots of trees, and less than .1 percent leached through to the mineral soil.  In the experimental shifting cultivation site, we learned that fire consumed only the leaves and small twigs, and that most of the forest nutrients remained in the trunks of trees lying on the ground.  After two years, the yield of manioc in the plots declined sharply, not because of loss of nutrients, but because of phosphorus being immobilized by the iron in the lateritic soils.  Application of leaf litter from the surrounding forest released organic acids that mobilized the phosphorus and allowed the forest to regenerate once the site was abandoned.

After the San Carlos project, I was involved in numerous tropical agroforestry projects in Thailand (taungya agriculture), Costa Rica (forest succession), Mexico (watershed studies) , and Brazil (mixed species plantations).  The overlying theme was that organic matter supplied by trees enabled nutrients to be recycled by economic crops. I also had graduate students involved in two massive deforestation projects in the Amazon of Brazil.  One was the Jari project where an area the size of Connecticut was cut down and burned. In contrast to shifting cultivation, the logs would burn for weeks until nothing was left but bare soil. The clay and sand was then planted to a monoculture of pulpwood.  Disease and nutrient losses devastated the project, and it was sold off in the 1990s for $1.00.  The other was deforestation to supply firewood for iron smelters for the Carajas mines, where at least there was an effort at reforestation of native species.

While it was fun to do science in remote regions of the world, it was clear that science alone could not solve the problems of tropical deforestation.  A broader perspective is needed.  I was fortunate to have several students do their research in Political Ecology, that is, the study of relationships between political, economic and social factors with environmental issues and changes.  Yunnan China (forest restoration policy forced indigenous farmers off the land);  Bocas del Toro Panama,(intensive cocoa cultivation displaced traditional sustainable production);  Pernambuco Brazil (Landless Workers' Movement); Transamazonica Brazil (Participatory Action Research for sustainable resource management).  My most intensive experience was in the Brazil nut forests near Maraba, Brazil, learning about the traditional culture that sustained the forest and the battles between the castanheiros (Brazil nut collectors) and the loggers and ranchers who cleared the land. 

I continued my tropical studies throughout the 1990s, but took an opportunity to buy a 100 acre farm near Athens Georgia. Then I asked myself, what am I going to do with this farm?  I took a tour of organic farms throughout Georgia and was amazed at what I saw – the farmers were using methods that destroyed their soil organic matter, the very resource they needed to conserve. I decided to dedicate the farm to research and education on methods of soil restoration – building up the soil organic matter that had been destroyed by a hundred years of cotton farming.  We called the farm “Spring Valley Ecofarms” to emphasize the fact that we were researching methods of cultivation that used the services of nature rather than chemical additives. 

One of the most striking discoveries I made on the farm was the similarity of the soils in the Georgia Piedmont and the lowland Amazon rain forest – both soils are highly weathered, leached of nutrients, and sustainability depends on the maintenance of a topsoil and litter layer rich in organic matter. Photographs of the soil types and discussion of management implications are given in "History of Ideas" in the History page of this website..

During the 1990s, “sustainability” became a buzzword for ecologists and much of the public.  I told my classes that farming at  Spring Valley (see “Application page in this website) was “sustainable agriculture.”  But some of the advertisements of industrial agriculture that claimed they promoted “sustainable agriculture” made me realize that “sustainability” has the same problem as “conservation”.  It means anything anybody wants it to mean.  The problem even extends to organic agriculture, where some of the techniques used by organically certified growers are clearly not sustainable. 

We need a definition that is not just opinion, but is scientific.   That realization led to my first effort at a definition: Sustainable agriculture is agriculture that maximizes energy use efficiency by minimizing “energy waste”, another term for pollution.  The definition, derived from Odum and Pinkerton (1955),  was first published in Jordan (2013). Feedback from readers suggested that I describe more fully the derivation.  I have done so here in the "Theory" web page under Energy Use Efficiency and Sustainable Agriculture. Following the article is an opportunity for all concerned to blog in support or against the definition, and for those who oppose, to present a definition that is not circular or religious.

Jordan, CF (2013). An Ecosystem Approach to Sustainable Agriculture.  Springer Verlag, Heidelberg
Odum HT, Pinkerton RC. 1955. Time's speed regulator: The optimum efficiency for maximum power output in physical and biological systems. American Scientist 43: 331- 343.

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