Cognition Index | Virtual Library
| Magazine Rack
Search | Join the Ecological Solutions Roundtable
COG Organic Field Crop Handbook
1.1 Misconceptions and Implications
The previous chapter explained some of the ecological principles on which organic agriculture is based. This chapter refers to some of the misconceptions widely held by those who do not understand these principles and looks at some of the implications of putting these principles into practise on an organic farm.
A phrase often heard is that organic farming is "farming without chemicals". In fact, organic farmers try to avoid direct or routine use of readily-soluble chemicals and all biocides whether naturally occurring or not. If it is necessary to use such substances, those that are least environmentally-disruptive are chosen.
Another misconception is that organic farmers merely substitute "organic" inputs for "agro-chemical" ones. In fact, the emphasis is on a carefully-designed crop rotation to build up soil fertility and to control weeds, pests and diseases. Additions of composted manure and other amendments are used when appropriate during the rotation.
2. Environmental sustainability
Organic agriculture makes positive contributions to long-term environmental sustainability by addressing the concerns about the loss of finite natural resources, environmental pollution of ground and surface water, intensive energy use and loss of natural habitats and species.
Protection of the soil is fundamental because the preservation of soil structure and soil life is essential to the working of an organic system. Organic farming involves techniques that minimize soil erosion. These include:
maintaining a crop cover, or crop residues, on the soil surface;
avoiding annual cultivation on slopes subject to erosion;
using strip cropping (alternating forage stands with other crops);
avoiding overgrazing by livestock;
improving soil structure, and hence resistance to erosion, through increasing organic matter and biological activity in the soil; and
eliminating highly-soluble fertilizers and synthetic pesticides, both of which can be toxic to many soil micro-organisms and, when used over time, contribute to the breakdown of soil structure.
Any field that shows evidence of significant soil erosion cannot be considered part of an organic food production system.
Studies have shown that for every unit of food produced, organic production systems use 50-80 per cent of the fossil energy used in conventional systems even when additional fuel for weed control cultivations is taken into account. However, this may not be the case in all fruit and vegetable operations.
Preservation of potable water supplies is an essential part of a sustainable agriculture system. Pollution of aquifers by nitrates and surface water by nitrates and phosphates is increasingly common in agricultural areas. Synthetic pesticide residues and other pollutants are also detected more frequently in the water systems. On an organic farm, water supplies are safeguarded by:
avoiding practices resulting in soil erosion;
practising proper storage, composting and application of animal manure;
avoiding having more livestock than the farm resources can handle;
eliminating the use of highly-soluble, synthetic fertilizers and synthetic pesticides;
increasing nutrient cycling on the farm utilizing the available nutrients and thereby avoiding runoff of the excess; and
improving soil structure and nutrient holding capacity.
Organic farmers increase soil fertility without the use of synthetic fertilizers. The techniques used include:
carefully-designed crop rotations;
addition of organic matter;
increasing the population of soil microorganisms through applications of composted manure;
eliminating highly-soluble fertilizers and synthetic pesticides, both of which significantly reduce biological activity in the soil when used over time;
minimizing tillage operations damaging to soil life; and
adding ground rock powders only when required.
These practises result in increased biological activity in the soil, and hence increased nutrient reserves (see Chapter 1.4, The Soil Ecosystem, for a more detailed explanation).
Other contributions to long-term environmental sustainability include reduced greenhouse gas emissions (nitrous oxides from synthetic nitrogen fertilizers and carbon dioxide), preservation of wildlife habitats and preservation of genetic diversity through use of more and, sometimes, less popular cultivars and species.
[photo 1.1 general farm view, no caption]
3. Productivity and economic sustainability
A sustainable agriculture system must, by definition, meet the needs of the present generation without jeopardizing the needs of future generations. It must also be economically-sustainable to the farmer, and to society as a whole.
With little data available from Canadian farms, it is difficult to generalize about potential yields from an established organic farm compared to a conventional one. For some crops, organic production systems on average equal conventional yields per hectare and some organic farmers are achieving yields higher than the conventional average. However, a 1989 study in Saskatchewan reported cereal yields averaged 80 per cent of conventional production. Yields tend to increase with the number of years under organic management but, during the early stages of conversion, some farmers have reported drops in yields of up to 30 per cent.
Global warming is creating increasingly-unpredictable weather patterns in Canada. Studies have shown that organic crops have higher pest and disease resistance and produce higher yields than conventional crops when under stress caused by drought, heat, excessive rain or unseasonably-cold weather.
Cost of production
Organic production systems place much less emphasis on purchased inputs. Synthetic fertilizer and pesticide purchases are eliminated, although some costs, such as seed purchases for cover crops and labor, may increase. On balance, input costs are lower on organic farms.
Organic farming methods replace herbicides with mechanical cultivation and other management practices to provide weed control. This has the potential to increase tillage requirements, and hence costs. In practise, this has not been the case. By improving soil structure and with good management practices, organic farmers have discovered that they require no more, and in some cases less, tillage than their conventional neighbors.
Markets and net farm income
Organic markets and delivery systems are not yet fully developed. Some organic producers receive premium prices for certified organic crops; others sell through conventional channels and receive no premium. In either case, the bottom line for the organic farmer is that net farm income is generally equal to, or better than, an equivalent conventional farmer. Data from the Saskatchewan study suggest that even if yields dropped to 60-70 per cent, income would be comparable.
Arden-Clarke, C., The Environmental Effects of Conventional and Organic/Biological Farming Systems, Oxford, U.K., Political Ecology Research Group, 1988, 2 vols.
Lampkin, Nicolas, Organic Farming, Farming Press, Ipswich, U.K., 1990, 701 pp.
Oelhaf, Robert C., Organic Agriculture, Economic & Ecological Comparisons with Conventional Methods, Montclair, NJ, Allanheld, Osman & Co., 1978, 271 pp.
Rutherford A. & Gimby M., "The Viability of Organic Farm Practices", Synergy, Vol. 3, No. 2, 1991, pp. 23-26
U.S. National Research Council, Alternative Agriculture, Washington, D.C., National Academy Press, 1989, 448 pp.
Copyright © 1992 Canadian Organic Growers. Inc
Reprinted with permission. All rights reserved.
How to order the COG Field Crop Handbook:
Info Request | Services | Become EAP Member | Site Map
Give us your comments about the EAP site
Ecological Agriculture Projects, McGill University (Macdonald
Ste-Anne-de-Bellevue, QC, H9X 3V9 Canada
To report problems or otherwise comment on the structure of this site, send mail to the Webmaster