study by researchers at McGill University and the University of Minnesota that compares organic and conventional yields from 66 studies and over 300 trials. In extrapolating the study's findings to the charged question of how to feed the world, more than a few got it all wrong.
The core finding of the study is that “yield differences [between organic and conventional] are highly contextual, depending on system and site characteristics.” In other words, sometimes organic does better, sometimes conventional does. In fact, the sheer variety of comparisons led Mother Jones columnist Tom Philpott to observe that the study “like a good buffet… offered something for every taste.”
For example, yields of fruit and oilseed crops showed no significant difference between organic and conventional, while conventional cereal crops and some vegetables produced higher yields than organic counterparts under certain conditions. With irrigation, conventional averaged 35% higher yields than organic (with the authors acknowledging that organic systems were mostly compared to high-input commercial systems), but this difference dropped dramatically under rain-fed conditions (the reality for most small-scale farmers around the world)—confirming other studies that have demonstrated the superior water-holding capacity and water infiltration characteristics of organic systems.
Seufert et al.'s intense scrutiny of a relatively small number of studies (66) is intriguing, but—media hype aside—the study doesn't really tell us which systems are better suited to providing healthy nutritious food for all in the 21st century. And to the authors' credit, they acknowledge that.
Yields don’t tell us how to feed the world
But let's cut to the chase. The animating question behind these "organic vs. industrial ag" debates is how to feed the world. Never mind that every study worth its salt points to poverty and inequity as root causes of hunger.
We know that agroecological farming can double global food production, and that investing in ecological farming is one of the best ways to improve rural communities’ food and livelihood security in developing countries. We also know that it’s not just how we cultivate our food that matters. The drivers of global hunger have everything to do with global trade, investment and ownership rules. Rewriting these rules, reining in corporate power and restoring democratic control over our food and farming systems are three of the most important ways we can fight hunger. Several of my colleagues have written an excellent piece addressing these points, carried yesterday by Huffington Post.
While any farmer will tell you that getting good yields is always desirable, a narrow fixation on yield measurements tends to blind policymakers to the bigger picture. Seufert et al. get this. They write:
Yields are only part of a range of economic, social and environmental factors that should be considered when gauging the benefits of different farming systems.So Scientific American’s headline to its coverage of the Nature piece, “Will Organic Food Fail to Feed the World?” was a disappointing mischaracterization of a paper that led to no such conclusion.
In fact, Seufert et al. make an excellent case for increasing funding for organic farming research, to better understand how these systems already work so well and to identify "improvements in management techniques" that "may be able to close the gap between organic and conventional yields." What always amazes me is how close organic systems are to conventional in yield, in the absence of meaningful federal research, development and extension support for organic. (Philpott reports that less than 1% of USDA research funds go towards organic systems, with the other 99% going towards industrialized agriculture—a tiny improvement on the 0.1% of federal research monies designated for organic previously documented by the Organic Farming Research Foundation.)
I asked University of Michigan Professor Ivette Perfecto (a co-author on the seminal 2007 Badgley et al. paper examining organic farming's contributions to the global food supply) what she thought of the piece in Nature. Her reply:
Although it is useful for understanding what are the factors that may limit productivity of organic and conventional systems, the restricted selection of the studies limits its applicability to the real world. There are very few studies from developing countries and none that compares organic agriculture with the conventional systems practiced by small-scale farmers.
What our study demonstrated was the potential of organic agriculture in developing countries for achieving yields similar to the so-called "best conventional practices" but without the negative environmental impacts of conventional agriculture.
Having recognized that conventional agriculture is simply not an option for the 21st century, loaded as it is with intolerable costs to our children’s health, our soil, water, biodiversity and even ecosystem function — shouldn't we be focusing instead on what investments are needed to bring organic systems to scale?