A version of this post originally appeared on U.S. Food Policy.
The journal Nature recently had an interesting meta-analysis -- or quantitative literature review -- about yields from organic agriculture. It's called "Organic farming is rarely enough," and the accompanying summary says, "Conventional agriculture gives higher yields under most situations." This is probably true.
The evidence Walsh presents fails to support the headline, though the article does begin with two good points: Organic agriculture does often produce less food per acre (see the Nature article above). And environmentalists should care about efficiency. Getting more output for lower resource cost is good environmentalism.
Mostly, though, Walsh repeats common overstatements of the advantages of conventional agriculture. He writes, "Conventional industrial agriculture has become incredibly efficient on a simple land to food basis. Thanks to fertilizers, mechanization and irrigation, each American farmer feeds over 155 people worldwide."
But environmentalists discussing conventional agriculture should also remember several key themes.