My friend Dr David Tribe from Melbourne University has just started his own blog, click here. Congratulations David!
I was scrolling through his recent posts and there is a great paper on organic farming, download file. Well it provides good quantitative comparative data on yields, nitrogen inputs, and nitrogen leaching for conventional and organic systems for trials in Norway, Switzerland, Sweden and Australia.
It is a pity they don’t include the data from the Rodale Institute in the US.
Scott Kinnear, a Director of The Biological Farmers of Australia and Victorian Greens Candidate, and others, often quote the trials from the institute as evidence that that organic farming systems are superior to conventional systems and in particular that they give a higher yield.
Indeed Kinnear claims as much on page 9 of a recent speech titled How Organics and Slow Food will Feed The World:
“Organic farming in the US yields comparable or better than
conventional industrial farming, especially in times of drought”.
The only example of this that I can find is a paper titled The performance of organic and conventional cropping systems in an extreme climate year, by Don Lotter, Rita Seidel, and Bill Liebhardt of the Rodale Insitute. They write:
In five out of six of the drought years during the 21 year experiment, corn yields were significantly higher in the organic treatments than those in the conventional treatment. The 1999 drought year being far more severe, results were more complex, and showed differences between the two organic crop systems.
Rainfall during the 1999 crop season totaled only 41% of average. The critical month of July had only 15 mm of rain, about 17% of the average. Crop yields were reduced to less than 20% in corn and 60% in soybean. Most farmers would have abandoned such a dismal corn crop; however, this kind of stress can expose differences between crop management systems that mild stress conditions cannot.
So if you don’t mind a really dismal yield, and if in drought, well you could go organic.
Otherwise, as the GMO Pundit, Dr Tribe says:
A review of farming performance in practice shows that for the same crop yield, organic farming requires more land than is needed with conventional farming with synthetic fertiliser.