How we produce food is of environmental importance because all agriculture has some impact on ecological systems. It is obvious that the growing or raising of domesticated plants and animals makes use of the natural carrying capacity of a landscape by replacing native (and sometimes endemic) species with human manipulated ones. Agricultural systems react to natural processes much like natural ecosystems. They of course interact with soil: growing too much of any one crop in one space without replenishing the nutrients that crop uses can lead to nutrient depletion; plowing and exposing soil, and overgrazing, can lead to accelerated erosion. Farms interact with water: irrigation is often (but not always) necessary to grow some crops, and water must come from somewhere like underlying groundwater, lake or river, with it's extraction potentially disrupting the hydrological cycle and aquatic ecosystems and requiring energy; heavy irrigation can raise the salinity of soil to the point of it becoming toxic to most plant life; agricultural inputs in the form of fertilizer (i.e. manure or synthetic chemicals) and pesticides often pollute –ground-water; soil, if it doesn’t get a supply of organic matter becomes sterile. And all processes of planting, caring for and harvesting food require energy, be it manual labour (human or animal) or mechanical; the source and of this energy (oil for machines, food for animal and human labor) and by-products (ex. GHG emissions) of course will have implications. Finally, we know that farming involves taking up natural landscapes and resources and devoting them to anthropocentric utility.
Thus, if as a global society we want to conserve natural ecosystems, we need to try and feed ourselves utilizing limited amounts of space, and to use that space sustainably. Many different schools of thought exist on how best to utilize farmland towards this goal, and this is one reason why different styles of farming exist.
It's worth pointing out that before "The Green Revolution," which has been a process of applying a certain planning paradigm, chemical fertilizers, pesticides, and machinery to farming, that all agriculture was organic – meaning before these modern technologies, all techniques for sustaining or increasing crop yield were biological/ecological in nature. So organic farming used to "feed to world."
It is also worth pointing out that many different people have different definitions of what organic farming is and isn't, and any claim or study has to be straightforward about what parameters are used. For example, consider the technique of tilling/plowing soil, and its rival "no till" agriculture. Many farmers mechanically disturb soil to control weeds and loosen it up for planting; other farmers avoid this, citing that it accelerates soil erosion. Dennis Avery, a senior fellow for the Hudson Institute in Washington DC and the director for Center for Global Food Issues, stated in The Star Tribune (a Minneapolis-St. Paul newspaper) on September 5th, 2007 that "organic farms… refuse to use the low-till farming systems that protect soil most effectively." He was speaking in relation to a situation where severe flooding caused mudslides in a hilly area of rural Minnesota, and claimed that organic farms suffered more heavily than conventional farms, because most "conventional" farms in the area "[use] low-till systems [that] depend on herbicides to control weeds, but the organic farmers won't use 'synthetic' pesticides. They choose, instead, to use the old bare-earth farming systems, with plows and mechanical cultivators that invite erosion." Avery has written quite a lot on agriculture, and his consistent argument is that organic farming is not effective or sustainable. Yet his claims that "organic farmers refuse to use no till" or that "no-till employs use of pesticides" reflects a severe misunderstanding or slandering of the facts; one can easily contest his claims by simply google-searching "organic no-till." One website that pops up is that of the "North Carolina (State U) Organic Grain Project" which has done research into organic no-till techniques that use cover crops and mulching to control weeds, and doesn't involve use of chemical herbicides. In fact even I writing this sentence have worked on multiple organic farms and gardens that never disrupted soil layers or left the surface exposed to sun, rain, or wind. I will bring up these case studies later.
No-till is just one example of a farming technique which is based on basic ecological knowledge and can be used on: small-scale, non-mechanized non-chemical polycultures (Permaculture farms); organic farms that don't use chemicals but still tend to be large-scale and mechanized; "conventional" farms which grow one or few crops and rely on machines and chemicals; or any other type of soil-based plant-farming system. Some other ecological strategies that can be applied universally (to all sizes of plant-farms) include: Integrated Pest Management (IPM), which involves a variety of techniques to confuse or deter pests, or provide habitat for pests' predators – IPM is used to reduce or eliminate reliance on pesticides. And crop rotation is another ‘organic’ soil-nutrient management technique, which can be used on simplified or diverse, square foot or multi-thousand acre agro ecosystems. Examples of crop rotation include altering between corn and soybeans (beans replace nitrogen corn uses); or occasionally using a field as pasture (thus bringing manure on site). Either of these practices could be considered organic farming techniques regardless of where they are applied; but they are not the end-all of organic farming.
Some farmers go further to minimize industrial inputs, reduce their local ecological impacts, and increase the ecological resiliency of their agricultural ecosystem. One technique I want to highlight specifically is companion planting / intercropping: placing many plant or animal species in proximity to make use of mutualistic relationships. A common example of this is The Three Sisters, a traditional pre-colonial North American polyculture: corn, beans, and squash planted together. Corn requires more nitrogen than many other crops, and is a tall, strong grass; beans (and other legumes) have a symbiotic relationship with soil-dwelling bacteria which fix nitrogen; and some bean species are vines which need something to climb; plants in the squash family grow close to the ground, shading and protecting soil, and potentially deterring mammalian pests with their spiky vines. Together, they grow quite effectively, although such a system could not be harvested by one person with one machine the same way a monoculture could. (And, no easily available studies talk about the quantitative yield when all three are grown together, compared to if grown separately).
The general purposes of companion planting include: limiting space for weeds; IPM; reducing water evaporation; using sub-surface and vertical space efficiently (different plants prefer more or less sun and wind, and send their roots to different depths for water and nutrients), thus being able to grow plants densely; nutrient exchange (for example, legumes). This model can even be applied as far as mixing fruit and nut trees, perennial and annual vegetables, berries, herbs, starchy roots, grains, and even livestock – all together in one system. The claim is made often that polyculture organic systems result in higher biomass compared to any monoculture. And certainly polycultures have increased biodiversity of domesticated plant and animal species on site. Hypothetically, these two qualities working together can entail a pretty high yield coming from such a system. But do such organic farms actually grow more food per acre than monoculture/conventional farms?
This question is hard to answer. First off, one system is talking about straightforward, tangible yields of one crop or very few crops: with a field of just potatoes, you can easily say "we produced X pounds/bushels" or even give a calorie measurement. With a system of many crops, you may also know how productive it is by totaling up the weight of pears, walnuts, tomatoes, corn, cucumber, eggs etc. of that system. Yet, there is difficulty in comparing these two systems and saying "A is more productive than B" because you are comparing one mass of one food to another mass of many foods; you could do a comparison of how many calories each system has produced, but that leaves no room to talk about the vitamins or minerals one would get from plants within a polyculture. Either way, some attempts have been made to compare yields of organic versus conventional farming systems.
Some claims and studies talking about yield:
One heavily cited and contested paper is from Badgley et.al.(2006) a team of University of Michigan researchers. They analyzed 293 case studies (ranging in length from one season to twenty years) and compiled the data to form region- and food-type-specific "organic vs. conventional" yield ratios. Some notable findings include: in developing countries, 102 studies related to grain products showed an organic:conventional yield ratio of 1.573:1; also in developing countries the ratio for vegetables was 2.038:1 (based only on 6 studies); for developed countries 31 studies show the vegetable yield ratio to be 0.876:1; for world-wide fruit production excluding wine, the ratio was 2.080:1. In fact for the developed world, almost all data the team summarized showed a ratio <1 (i.e. that organic farming yielded less than conventional) as compared to almost all data for the developing world showing that organic systems were higher yielding. In the write-up of their study they suggest a reason for this: most developing world organic farms (which are not "certified organic" generally since they grow for local consumption) are small-scale and Badgley et.al suggest smaller farms tend to be densely planted and managed and thus produce more yield per area. They also touch on the question of polycultures (without directly linking it to farm size): citing a 1993 UN-FAO report they state "…many organic farmers use polycultures and multiple cropping systems… from which the total production per unit area is often substantially higher than for single crops."
Our organic-skeptic friend Dennis Avery has of course deconstructed parts of the Badgley et. al. report. In a September 2007 piece on his Centre for Global Food Issues website he claimed, amongst other things, that their study: presented yields from non-organic farms as organic; compared organic yields to non-representative non-organic yields; "doubled, tripled, even quintupled counting of organic yields from the same few research projects;" and omitted or construed non-favorable data. On that first point, Avery referred to data about rice yields using the System of Rice Intensification, an international initiative to make rice production more efficient and sustainable. Badgley et al considered it as an organic technique in their data summary, while Avery suggests it is not "organic" at all. They are both sort of right: the website of the project itself states "{SRI} is a methodology… changing the management of plants, soil, water and nutrients… leads to healthier, more productive soil and plants by supporting greater root growth and by nurturing the abundance and diversity of soil organisms." SRI production does not rule out pesticide usage for meeting acute needs (so Avery is right); but also focuses heavily on ecological means to build up soil fertility and thus plant health - hence Badgley et.al. consider SRI as organic in nature.
Still speaking about rice, David Suzuki and Holly Dressel have shed some light on yields and growing systems in Indonesia. They mention how government planners and corporations encouraged a transition from traditional ecological farming systems to Green Revolution (regular irrigation, chemical fertilizer, pesticide, hybrid variety) systems in the 1970s; this led to temporary increases in output, but over time yields dropped. An American systems ecologist hired by Bali's Department of Public Works to look into these trends found through modeling that: using traditional watering techniques and varieties of rice yielded 8.5 tons per hectare per year, averaging 17 tons over two years; Green Revolution techniques led to over 10 tons in the first year and then severe drops in the second year (Suzuki’s account doesn't give a number), leading to the "conventional" system have a lower cumulative output than the "organic" system (p.167). Some entirely different statistics from the same region point to similar trends: in 1987 the government of Indonesia stopped subsidizing pesticides and started restricting access to 57 rice-related pesticides. By 1990, national pesticide usage was down 50% and crop yield has increased 15% (p. 171). Of course the two events could merely be correlated and have no casual relationship; but it's interesting to note at least that yields didn't decrease – many anti-organic voices claim that halting pesticide usage would cause drastic yield decreases.
Suzuki and Dressel go on to highlight some other pro-organic stories, as this is their bias of course. One U.N.Development Program project took an organic "raised field" (raised-bed?) technique which was native to the Andes and applied it in Honduras, finding increases in (unnamed) crop yields from 400 kg a hectare to between 1200 and 1500 kg/ha. They also mention a study done by the World Resources Institute (a Washington DC think-tank) which reviewed sustainable agriculture projects affecting around two million households in the Third World, and found that farmers who switched from "industrial, high external-input" systems to "biodiversity-based low-input" organic polycultures apparently doubled yields of corn, sorghum and wheat (p. 172).
Speaking of the production of grains specifically, proponents of conventional agriculture often point out that the increased global food supply over the past century has been a direct result of Green Revolution techniques, and thus it could be very risky to try and wean farms off of chemical and mechanical support systems. Some studies from the developed world back up their theory:
o Avery (2002) points out that "Great Britain’s Cooperative Wholesale Association, which farms about 80,000 acres in both mainstream and organic modes, told a hearing of the British House of Lords in 1999 that it gets 44 percent less wheat from its organic fields."
o Avery (2007) "A recent organic farming "success" at the Rodale Institute achieved grain-equivalent yields from organic farming that were 21 percent lower and required 42 percent more labor. Such yields may be theoretically kinder to the environment, but in practice they would lead us to destroy millions of square miles of additional natural areas."
There are a couple of inherent downfalls in believing that these facts prove that organic farming is not up to the task. First off: monocultures in general are unstable ecosystems, and supporting them with externally-sourced chemical nutrients and defense mechanisms is of course going to have higher yields, faster, than trying to build up a healthy soil ecosystem with organic techniques and implement IPM strategies.
In other words, comparing a conventional monoculture to an organic monoculture is an unfair comparison, like comparing a body builder who uses steroids to one who doesn't. Yet, in the long run, the natural body builder might prove as strong:
o A Cornell U study analyzed a 22-year-long Rodale Institute project which compared three corn- and soybean-producing systems: one conventional; one organic fed by manure; and one organic with a three stage rotation. Overall, all three produced similar results. The organic systems produced less corn in the first four years, caught up, and outperformed the conventional system in drought years. The organic systems increased carbon content in soil from 12 to 25 %. The organic systems were more labor-intensive due to work involved in including organic fertilizer and IPM techniques; but used 30% less actual energy (due to less petroleum inputs, likely) (Lang 2005)
- POLYCULTURES: organic farming's ability to feed the world is likely to be better demonstrated in polyculture and small-scale systems: Howden (2008) a journalist writing a piece called "Organic farming could feed Africa" points to U.N. Environment Programme research which "suggests that organic, small-scale farming can deliver the increased yields which were thought to be the preserve of industrial farming." He goes on "An analysis of 114 projects in 24 African countries found that yields had more than doubled where organic, or near-organic practices had been used. That increase in yield jumped to 128 per cent in east Africa."
One other point that many organic-skeptics state is that: while a well managed organic farm may be able to produce high yields, it's difficult to maintain soil fertility. Meisner (2007) refers to research he himself did in Bangladesh. He concedes he thinks organic methods are better for long term soil fertility, but are difficult to implement because "a six-tonne rice crop in the peak season requires 100 kg of nitrogen… [With] good quality manure, there would be about 0.6 per cent nitrogen in the material; thus, requiring 17 tonnes per hectare to produce a six-tonne rice yield" and cites that manure is not cheaply available in those quantities in Bangladesh, nor is it easy to bring on-site.
Meanwhile, proponents of organic techniques suggest it's not difficult to incorporate "green manures" (ex. legumes, clover) into a farming system, and is rather ideal: David Blume (2007) has stated that over a 9-year period of planting and managing a densely planted organic polyculture in California that use of cover crops and constant on-site composting led his soil to have "22% organic matter, with a cation exchange capacity (CEC) of over 25" adding for reference "most Class I commercial agricultural soil is lucky to hit 2% organic matter… with a CEC around 5." He suggests that this resulted in "yields were often 8 times what the USDA claims are possible per square foot." Blume goes on to talk extol the benefits of polyculture systems, stating (without evidence or links to any studies) that "with a polyculture, yields of 3-10 pounds of food per square foot are easy to come up with in most climates…. Commercial agriculture in California … routinely runs about 1.5-2.5 pounds per square foot per year across a wide variety of crop."
Conclusion: It is outside of the scope of this essay to definitively say "no" or "yes, organic farming can feed the world." We could say certain types of food may be grown better with conventional means, like wheat for example, whereas other crops like fruits, berries, and vegetables could be grown better in organic polycultures. Either way, we can't put all our eggs in one basket if we want to have a stable and accessible global food supply. Farmers need to (and do) engage with scientists to study a variety of techniques to meet out current needs without compromising the future potential of our agricultural landscapes. This means we have to rethink the contention around food supply: it's not a debate of 100%-conventional versus 100%-organic, but rather a debate of which techniques are appropriate for certain places. If in fact small-scale polycultures are more productive, but need more hands-on human attention, then they are appropriate for a society that can or does have a high proportion of people involved in food growing. But to maintain a society with urban centers and complex institutions, we of course can't have a situation where everyone has to be engaged in small-holding subsistence agriculture; we need some farming systems which produce a high surplus per farmer. Thus, decisions about how humanity feeds itself have to be driven by a combination of scientific knowledge and social, political, cultural, and economic concerns; these decisions need to be made democratically, on the local level; and have a certain measure of adaptability.
Sources are in order of when they were cited in essay:
Avery, Dennis. (September 5th, 2007) The consequences of organic farming: Recent rains washed out land made prone to erosion by the practices that were employed. Star Tribune online.
NC State U. (2005) Organic Grain Production: Organic Soil Fertility: Tillage Practices. North Carolina Organic Grain Project,
Badgley, Catherine et.al. (2006). Organic agriculture and the global food supply. Renewable Agriculture and Food Systems 22(2); 86-108, Cambridge U Press, July 2007.
Avery, Dennis. (September 6th 2007) "Organic Abundance" Report Fatally Flawed.
The System of Rice Intensification, homepage, Retrieved April 12th 2009.
Suzuki, David and Holly Dressel. (2002). Good News for a Change. Greystone Books, Toronto.
Avery, Dennis. (April 3rd 2002). The Most Sustainable Farming in History Gives the World Its Finest Food Choices: A Response to The Johns Hopkins University Authors. The Center for Global Food Issues.
Avery, Dennis. (2007) Saving Nature's Legacy Through Better Farming. Fall 2007 "Issues in Science and Technology" Online.
Meisner, Craig. (2007). Why organic food can't feed the world. Cosmos Online, Opinion, September 24th 2007.
Lang, S. Susan. (2005). Organic farming produces same corn and soybean yields as conventional farms, but consumes less energy and no pesticides, study finds. Cornell U News Service, July 13th 2005.
Howden, Daniel. (2008). Organic farming 'could feed Africa: Traditional Practices increase yield by 128 per cent in east Africa, says UN. The Independent, October 22nd 2008.
Blume, David. (2007). Food and Permaculture. A response to "Of course you couldn't feed the world with… Permaculture." Permaculture.com article.
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