Organic Agriculture: Deeply Rooted in Science and Ecology
Eliot Coleman
Grist
Coleman’s Four Season Farm: Start with biodiversity and well-nourished soil, add some appropriate technology, then harvest lots of healthy food. Photo: Barbara DamroschOrganic farming is often falsely represented as being unscientific. However, despite the popular assumption that it sprang full born from the delusions of 60s hippies, it has a more extensive, and scientifically respectable, provenance. If you look back at the first flush of notoriety in the 1940s, the names most often mentioned, Sir Albert Howard and J. I. Rodale, rather than being the initiators, were actually just popularizers of a groundswell of ideas that had begun to develop some 50 years earlier in the 1890s.
A growing coterie of farmers, landlords, scientists, and rural philosophers in both England and Germany had begun questioning the wisdom of the chemically based agriculture that had grown so prominent from its tiny beginning in the 1840s. Advances in biological sciences during the late 19th century, such as those that explained the workings of nitrogen fixation, mycorrhizal association, and soil microbial life supported their case. Those new sciences set the stage for a deeper understanding of natural processes, and offered inspiration as to how a modern biologically based agriculture might be formulated.
These new agriculturists were convinced that the thinking behind industrial agriculture was based upon the mistaken premise that nature is inadequate and needs to be replaced with human systems. They contended that by virtue of that mistake, industrial agriculture has to continually devise new crutches to solve the problems it creates (increasing the quantities of chemicals, stronger pesticides, fungicides, miticides, nematicides, soil sterilization, etc.) It wouldn’t be the first time in the history of science that a theory based on a false premise appeared to be momentarily valid. Temporary functioning is not proof of concept. For example, if we had a book of the long discredited geocentric astronomy of Ptolemy, which was based on the sun revolving around the earth, we could still locate Jupiter in the sky tonight thanks to the many crutches devised by the Ptolemaists to prop up their misconceived system. As organic agriculture has become more prominent, the orthodoxy of chemical agriculture has found itself up against its own Galileo. It will be interesting to see who recants.
The new thinking in agriculture was focused on three issues — how can long lasting soil fertility be achieved? How can pest problems in agriculture be prevented? How can the nutritional value of food crops be optimized? By the 1940s the answers to those questions had coalesced into a new biologically based concept of agriculture that can be simply stated as follows:
- Soil fertility can be raised to the highest levels by techniques that increase the percentage of soil organic matter, by rotating crops and livestock, and by maintaining soil minerals through using natural inputs such as limestone and other finely ground rock powders.
- The plant vigor resulting from doing #1 correctly renders plants resistant to pests and diseases.
- The plant quality resulting from doing #1 correctly provides the most nutritious possible food for maintaining human beings and their animals in bounteous health.
All three begin with and depend upon how the soil is treated. But the fertility of that crucial soil factor is not a function of purchased industrial products. It evolves from intelligent human interaction with the living processes of the earth itself. These are processes that are intrinsic to any soil maintained with organic matter. They are what the earth does. I am puzzled by how the practical success today of the many farms managed on biological rather than on chemical lines can coexist with the striking lack of interest (antagonism actually) from scientific agriculture in exploring why these farms succeed. The foundation upon which our Maine farm operates — a sense that the systems of the natural world offer elegantly designed patterns worth following — appears to be an indecipherable foreign language to agricultural science.
Skeptics have often misrepresented a biologically-based agriculture as if it is nothing but the substitution of purchased organic inputs for purchased chemical inputs. Even if there were evidence to document the rationale for a substitution philosophy, it would lose on the grounds of economics alone. Both bone meal and dried blood, for example, two popular “organic” fertilizers, are prohibitively expensive on a farm scale. Furthermore, such substitution thinking is not pertinent to the actual objective of a biological agriculture — namely the development of sustainable, farm-generated systems for maintaining soil fertility. The concern is not the substitution of one fertilizer for another but rather the long-range practical and economic viability of farming practices. Supplies of blood and bone meal are no more assured than are supplies of chemical fertilizers that derive from finite and dwindling resources. We cannot depend upon an agriculture that relies on inputs from either source. What can be depended upon, however, is a biologically focused farming system that bases fertility maintenance on proven cultural practices with the addition of locally available waste products.
Organic intellectual: Eliot Coleman, with produce.Photo: Barbara DamroschAmong those cultural practices I include:
Crop rotation: Firmin Bear of Rutgers stated that a well-planned crop rotation was worth 75 percent of everything else the farmer did.
Green manures: Deep-rooting legumes not only fix nitrogen, penetrate hardpan and greatly increase soil aeration but also bring up new mineral supplies from the lower depths of the soil.
Compost making: Of all the support systems for the biological farm, none is more fortuitous than the world’s best soil amendment, compost, which can be made for free on the farm from what grows thereabout.
Mixed Stocking: Raising animals and crops on the same farm has both symbiotic and practical benefits. The crop residues feed the animals and the animal manures feed the soil.
Ley Farming: The fertility of land plowed up for row crops after 3 to 4 years in grass/clover pasture is close to that of virgin soil because of the enormous amount of plant fiber added by the perennial plant roots.
Undersowing: Establishing a green manure crop underneath the growing cash crop can often double organic matter production in the course of the year without any effect on the cash crop.
Rock Powders: The slow, measured availability to plants of mineral amendments (calcium, phosphorus, potassium, etc.) added to the soil as ground rock powders mimics the availability from natural soil particles.
Enhancing biodiversity: This includes practices such as growing a wide range of crops, sowing pastures with many different forbs in addition to grasses and legumes, carrying a mixture of livestock, establishing hedgerows for wildlife habitat, and so forth. The more components involved, the more stable the system. The aim of a biologically based agriculture is to cultivate ease and order rather than battle futilely against disease and disorder.
But, can you really farm that way? Can a successful agriculture be conducted by simply combining the known effects of natural processes with the management provided by intelligent human understanding of how to nourish those processes? If such an agriculture can work and could be made universal, then this new agriculture would be truly sustainable and have the power to transform the world. Back in 1967, when I began farming, none of us paid attention to whether agricultural science approved of our biological approach. We started farming with compost and cultural practices because the ideas made sense and, lo and behold, they worked. Alternative agricultural research today is showing that we were pretty astute. Studies are appearing almost too fast to read them all.
For example, the importance of soil organic matter is more appreciated every day even though, as a recent study concluded, “it is arguably the most complex and least understood component of soils.” The bioactive humic substances produced by earthworms in compost have been found enormously valuable at enhancing root growth and availability of nutrients. Other work with composts has determined that they can control plant diseases through making the plant more resistant — what Harry Hoitink of Ohio State calls “Systemic Acquired Resistance.” The entomologist T. C. R White has explained how the effect of stressful growing conditions “upsets the metabolism of the plant in such a way as to” increase “survival and abundance of herbivores feeding on” the plant even though these “changes may often not be sufficient to produce visible signs of stress in the plant.” The conclusion is that plants not genetically resistant to a pest can be made so through better growing conditions. But even genetic resistance makes no difference if negative growing conditions inhibit the expression of the genes. In USDA research to determine why tomatoes growing in mulch of vetch green manure were more disease resistant and longer lived than identical tomatoes with black plastic mulch, Kumar et al. found that the genes for longevity and resistance were not ‘turning on’ in the sections without the vetch mulch.
Nutritionists, to their dismay, have found what they call “dilution effects” in modern chemically adapted crops. Breeding programs aimed to produce high yielding cultivars, combined with intensive chemical fertilization to push yields higher, have resulted in vegetable and grain crops that are no longer as nourishing because their limited root systems can’t absorb enough minor nutrients. The result is a “hidden hunger” caused by trace element deficiencies in those who consume those foods. The recent study by Brian Halweil, Still No Free Lunch, presents a very complete picture of the relationship between plant breeding, high chemical fertilizer use, and the decline in nutritional value of what we eat. A few forward-thinking scientists around the world are starting to look into biological issues, and they are finding that the system that biological farmers have been creating for the past 120 years is as good as they have claimed it to be.
How could these ideas have been so obvious, so logically presented, and yet so consistently ignored by the majority of agricultural scientists? Let me explain it metaphorically. Imagine if you will, an enormous tapestry hanging from the ceiling of a grand hall. The tapestry depicts the natural world in all its elegance. Subsoil and topsoil, plowed fields and green pastures, prairies and forests, valleys and mountains, sea and sky are all crisply represented. There are creatures large and small, birds and fishes, bacteria and fungi, predator and prey and the dynamic balances between them. You can also see farmers interacting harmoniously with that living world.