Organic can be the right choice for fruit, sometimes

This “Green Chain”column will be published in the Lake County Record-Bee on Tuesday.

The National Organic Program administers the O...

The National Organic Program administers the Organic Seal to products that meet the requirements. (Photo credit: Wikipedia)

“When the facts change, I change my mind. What do you do, sir?” – John Maynard Keynes.

Forgive me please for starting this month’s column with the same John Maynard Keynes’ quote as last month’s. But new facts have been brought to light.

I have long maintained that it is wrong-headed to always choose organically-produced foods over foods produced using synthetic chemicals and fossil fuels. I have previously pointed out the use of fossil fuels to produce pesticides and fertilizers and run machinery allows conventional farming to use less land than organic methods. And, when taken in aggregate worldwide, we spare wetlands, grasslands, forests, and sundry open spaces from being cleared for agriculture. Had farmers continued to use organic farming methods, they would have needed to exponentially increase the acreage under cultivation in order to increase production to meet demand. And since agriculture is the number one cause of deforestation, more acres under cultivation means a loss of biodiversity, which is the last thing proponents of organic agriculture want.

A newly published report in the journal Nature shows that I am incorrect, if only slightly. This new paper forces me to revise my statement. The new statement: it is generally wrong-headed to always choose organically-produced foods over foods produced using synthetic chemicals and fossil fuels.

The report is titled, “Comparing the yields of organic and conventional agriculture.” While I have admittedly only been able to access the abstract, the authors find that organic farming methods are indeed less efficient than conventional ones: anywhere from 5 percent to 34 percent less efficient. But they also state, “Under certain conditions—that is, with good management practices, particular crop types and growing conditions—organic systems can thus nearly match conventional yields.”

Those “nearly match” crop types they refer to are not, sadly, vegetable and grain crops, which provide most of the calories for the world’s populations. Organic yields for vegetable and grains generally fall one-third below the yields of conventionally grown crops. On the Nature website Melissa Gilbert paraphrases lead author Verena Seufert, “Cereals and vegetables need lots of nitrogen to grow, suggesting that the yield differences are in large part attributable to nitrogen deficiencies in organic systems.”

Some fruits, on the other hand, under ideal circumstances can produce up to 97 percent of the amount of conventional yields if they are planted in rotation with nitrogen-fixing legumes to replace the critical nitrogen in the soil. Still, this 97 percent only counts the yield of the fruit crop. It ignores the need to harvest a legume instead of fruit every other rotation. There is no such need with conventional methods, which can bring double the yield since farmers would not necessarily need to rotate to a legume.

We often wax nostalgic for the good old days. Somehow, those days were better and technology, on the whole, has been bad. We downplay the benefits. Stephen Budiansky, a former editor of Nature, writes that due to the use of technology “…the total land area of American farms remains almost unchanged from a century ago, at a little under a billion acres, even though those farms now feed three times as many Americans and export more than 10 times as much as they did in 1910.”

So, if you are concerned about preserving forests, wetlands, and open space, it is usually, but not always, wrong-headed to always choose organically produced foods over foods produced using synthetic chemicals and fossil fuels—if we’re talking about certain fruits, that is.

Sources:
Biello, David. ”Will Organic Food Fail to Feed the World?” Scientific American. April 25, 2012. (http://www.scientificamerican.com/article.cfm?id=organic-farming-yields-and-feeding-the-world-under-climate-change accessed 04/25/2012)

Budiansky, Stephen. “Math Lessons for Locavores.” NYTimes.com. Published: August 19, 2010. (http://www.nytimes.com/2010/08/20/opinion/20budiansky.html?_r=2 accessed 07/31/2011)

Gilbert, Melissa. “Organic farming is rarely enough: Conventional agriculture gives higher yields under most conditions.” Nature News & Comment. (http://www.nature.com/news/organic-farming-is-rarely-enough-1.10519 accessed 06/13/2012)

Seufert, Verena, Navin Ramankutty, and Jonathan A. Foley. abstract for “Comparing the yields of organic and conventional agriculture.” Nature (2012) doi:10.1038/nature11069 (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11069.html accessed 06/13/2012)

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