The whole point of organic farming is the soil. Farm in a way that your soil stays healthy – rich in organic matter, nutrients and microbial activity – and you can grow crops without the synthetic fertilizers and pesticides used in conventional farming.
Organic farmers use many techniques to improve their soil. They use compost and manure, rotate their crops and cultivate many kinds of plants. They use pesticides, but only some (mostly non-synthetic, with a few approved synthetics), and often only when other pest control methods fail.
But a lot of conventional farmers do a lot of those things too. When you shell out the extra money to buy organic produce, are you supporting the environmental benefits? I wanted to know, and that was probably one of the hardest questions I tried to answer in this column.
We do not have data on soil health or environmental pollution (in the form of soil erosion, nutrient runoff or greenhouse gases) that allow us to comprehensively assess all organic and conventional acreage and whether one type or the other is doing better, but scientists across the country are working on comparisons, so we have something to do.
Go ahead, and you’ll find that, yes, organic farming—which, for the purposes of this discussion, means agriculture certified to rigorous standards set by the United States Department of Agriculture—has significant environmental benefits.
One of the scientists working on the comparison is Michel Cavigelli of the USDA. He runs something I’d call an organic vs. conventional smackdown if we weren’t talking about the rarefied world of soil science. It’s a long smackdown (okay, let’s go), which began in 1993. The USDA farm in Beltsville, Maryland is testing five types of agriculture: two conventional and three organic. (Differences relate to crop rotations and types of tillage.)
Yes indeed. There is never a clear answer to a question like this when talking about something as complicated as agriculture. The first thing Cavigelli said to me was that “all things conventional are not the same, and all things organic are not the same” and then he went on to mention something about demons and details.
Nevertheless, some important differences between these five systems have come to the surface over the past 23 years.
Biological systems in the USDA test:
● Have more fertile soil.
●Use less fertilizer and much less herbicide.
● Consume less energy.
● Lock more carbon in the soil.
●Are more profitable for farmers.
●Have higher yields.
● Are best at reducing erosion (when a no-till system is used).
After speaking with several scientists who study the differences between the two systems, and after reading countless articles on the subject, I think it’s reasonable to conclude that while results obviously vary, this list is a representation reasonableness of the advantages of each system. (If you find other important and general claims for organic farming, check the source. Many organic organizations make such claims. It is perfectly reasonable for advocacy groups to focus on research that presents organic farming in its best light, just like mainstream groups focus on the benefits of efficiency and genetic modification of crops, but, for that, I tried to focus on the sources that have no skin in the game.)
I learned a few interesting things along the way. First, although I’ve heard many claims that no-till agriculture (growing crops without tilling the soil) can retain carbon in the soil (keep it out of the environment, where it contributes to climate change ), several sources have told me that it appears that the sequestered carbon is only in the top layer of the soil. Dig deeper and you won’t find any. Cavigelli’s organ systems, on the other hand, had sequestered carbon at much deeper levels.
But in looking at claims about carbon sequestration in organic systems, we need to look at the whole picture. Phil Robertson, a prominent Michigan State University professor, points out that much of this carbon is added to the soil in the form of manure. Which means that while there is more carbon in that particular soil, there is less where you took the manure. “It’s robbing Peter to pay Paul,” he said.
Robertson also said some tools that mitigate environmental damage aren’t available to organic farmers; one of them is genetically modified crops. Although reasonable people disagree about how the pros and cons of these crops balance out, Robertson, along with many scientists and farmers, argues that the two main types of GMOs – those that resist to glyphosate herbicide and those with an integrated structure. in an organic insecticide — can help reduce pesticide use.
Moreover, it is difficult for organic farmers to implement no-till. Without herbicides, the best weed control tool is tillage, which can lead to the erosion, nutrient runoff, and disruption of the microbial community that organic farmers work so hard to foster.
Overall, however, it’s pretty clear that organic systems generally have healthier soil and some environmental advantages over conventional systems.
But there is a problem. Environmental benefits are usually not the reason consumers are willing to pay extra for organic products. According to the Organic Trade Association (and other groups), consumers buy organic products primarily because they believe the products are better for their health: either more nutritious or safer. It is therefore not surprising that suppliers and advocates of organic foods often promote a product by implying that it is more nutritious or safer, a claim unsupported by most evidence.
Organic advocacy groups market safety and nutrition, as in the Organic Center’s “Complete Guide to Identifying Safe and Nutritious Foods” or the Environmental Working Group’s Healthy Child Initiative, touting “more scientific evidence than organic foods are more nutritious”. The labels of some organic products use the word “toxic” to describe the pesticides they do not use, despite the fact that some toxic pesticides (pyrethrin, for example) are allowed in organic farming. Although organic farming certainly uses fewer pesticides, and this is an environmental benefit, the preponderance of evidence indicates that trace amounts of pesticides in food are not harmful to human health. (Higher levels of exposure, such as those experienced by agricultural workers, are another story.)
Unfortunately, you can’t believe organic foods are more nutritious and safe without believing that conventional foods are less nutritious and safe, and that infuriates conventional food advocates. Sometimes this fury takes on a nasty edge – I’ve noticed some schadenfreude during outbreaks of foodborne illnesses linked to organic foods – but I understand where that’s coming from. Conventional foods are as safe and nutritious as their organic counterparts, and if consumers are told otherwise, they are misled and conventional producers are harmed.
And misinformation does nothing to improve the quality of public debate. On farms, in academic institutions, and in regulatory bodies, I’ve found that almost everyone thinks it’s helpful for farmers to employ and improve all kinds of practices. Feeding our growing population is a big job, and there are many constructive ways – organic and conventional, large and small scale, urban and rural – by which farmers are tackling it. We need everyone.
Sometimes it seems like every column I write has the same conclusion, but this is an important conclusion. If we want to make progress on food, we need a lot less of us than they do. The USDA Certified Organic Program – from its inception a marketing program, not an environmental initiative – has given organic farmers a way to earn a living (and farmers should earn a living) by connecting with like-minded consumers. like-minded and willing to pay a premium for a product that is grown in an often labor-intensive, low-yield way, and produces real environmental benefits.
It also gave consumers choice. For those worried about how most food is grown in this country, organic is a way to vote no. But if the undeniable benefits of organic are overshadowed by the negative of organic-conventional bias that impedes progress, we all lose.
Haspel writes about food and science and raises oysters on Cape Cod. On Twitter: @TamarHaspel. She will join Wednesday’s Free Range chat at noon: live.washingtonpost.com.