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Organic Agriculture Centre of Canada

The results of a 12-year study have shown that organic farming systems in the Canadian Prairies are energy winners in two out of three farming goals.

If the main focus of producers is to reduce non-renewable energy inputs, organic systems are far ahead. By not using synthetic fertilizers or pesticides, energy savings of about 50% were reported.

If the primary goal of producers is to increase energy use efficiency (energy produced per unit of energy consumed) organic systems with a mix of annual grains and perennial forages would be favored.

It is only in the third area, where the primary focus of farmers is to increase
net food production per unit of land, that conventional systems using inorganic fertilizers and pesticides are favored. These systems would work with a diversity of annual and perennial grain crops.

鈥淲e know organic management saves non-renewable energy,鈥� says Robert Zentner of Saskatchewan, lead author of the 鈥溾�� study, published in the European Journal of Agronomy.

鈥淏ut we also know the output from our organic systems is lower because yields are traditionally down,鈥� he said in a phone interview.

If energy savings were the only consideration, particularly in a world of increasing non-renewable energy costs and growing scarcity, then organic would be the obvious choice.

But in the larger picture, with populations continuing to grow, total food production also needs to be considered.

鈥淚f producers move more toward forage based or organic systems, net food production for human consumption will decline,鈥� states the study. 鈥淭his may be unacceptable in a world of growing food deficits.鈥�

Yet opting to maximize food production will require that non-renewable energy requirements remain high.

鈥淣o matter what issue you鈥檙e looking at, there are always trade-offs,鈥� says Zentner.

The long-term solution would likely be to have organic farming systems with low energy requirements producing quantities of food comparable to conventional systems.

Zentner says research in the United States has shown that under certain conditions and in some farming areas, organic yields can approach conventional output. 鈥淲e don鈥檛 seem to be there yet in Canada.鈥�

Part of the problem may be soils, weather and growing conditions. For example, in the non-renewable energy study, researchers were dealing mainly with a particular type of prairie soil under at times semi-arid conditions with a relatively short growing season. Though general findings would likely still apply, results in different areas would vary.

Another part of the problem is the lack of research in the past into increasing organic yields. Zentner notes that research into conventional farming has been carried out at an agricultural research facility in Swift Current since 1920, or for more than 90 years. Yet organic research has only been undertaken there in the past few years.

If more research is done, there鈥檚 a possibility organic systems in some parts of Canada could eventually have yields comparable to conventional systems, says Zentner.

He says many farmers are questioning a way of food production that relies on heavy use of synthetic fertilizers. 鈥淎 lot of it has to do with the increasing costs, but also the environmental impacts,鈥� he says.

鈥淚n many cases we鈥檙e talking about putting some limits on the environmental damage associated with our different management systems.鈥�

The 12-year study, which still has another six to go, looked at a wide range of systems and crops.

The study compared a matrix of nine cropping systems for the Canadian Prairies based on three levels of inputs: conventional high inputs, reduced where attempts were made to reduce inputs without reducing crop yields, and organic where input reductions were expected to reduce crop yields.

Input levels were combined with three levels of cropping diversity ranging from a low diversity system, to a diverse mix of annual cereal, oilseed and pulse grains, to a very diverse mix of annual grains and perennial forages.

The study suggests that producers would have flexibility to substitute inputs for each other to improve performance on other sustainability issues. The strength of the research is the developing body of evidence to guide such decisions.

This article was written by Steve Harder on behalf of the OACC with funding provided by Canada鈥檚 Organic Science Cluster (a part of the Canadian Agri-Science Clusters Initiative of Agriculture and Agri-Food Canada's Growing Forward Policy Framework).聽 The Organic Science Cluster is a collaborative effort led jointly by the OACC, the and industry partners. For more information: oacc@dal.ca or 902-893-7256.

Posted April 2011