While much of conventional farming is doing more harm than good to the climate, wheat may be an important crop for reducing greenhouse gas emissions.
So, would wheat still be such a dietary pariah if it could help to curb climate change?
According to a new paper published in the recent journal Nature Communications, we may want to give wheat another chance. “The study found that a combination of a few basic farming practices boosted wheat production and put heaps of carbon back into the soil–more than enough to compensate for the GHGs emitted in the process of growing it,” reports Civil Eats.
It’s been thought that wheat actually contributes to greenhouse gases by producing carbon, but the roots and stems of the plants that are left in the ground at the end of the growing season actually replenish carbon in the soil, which offsets emissions. Civil Eats explains: “That means reducing the climate impact of wheat hinges on maximizing soil carbon storage and minimizing inputs, all while growing as much grain as possible.”
The researchers farmed several dozen test plots, with four different cropping techniques, measuring the results. The test plots were either grown with “a three-year rotation of fallow-wheat-wheat, another of fallow-flax-wheat, a two-year rotation of wheat and lentils, and continuous wheat plantings,” reports Civil Eats. “What the researchers found surprised them: All of the plots had a negative carbon footprint.”
All of the wheat returned more carbon than was emitted, the researchers discovered. “In part, the researchers attribute this result to the way they calculated the total carbon balance; many previous studies failed to consider the role of soil carbon at all,” Civil Eats explains.
The researchers discovered that keeping the crops in the ground instead of fallowing the land (keeping it unseeded) was a hugely important factor in the decrease of wheat’s carbon footprint. But the researchers also noted the pressure of continuous planting, which can require carbon-intensive chemical fertilizers and pesticides. It turns out though, the lentils used in one of the test plot groups were hugely beneficial in the reduction of fertilizer, according to Civil Eats. “On average, fields planted with lentils required 30 percent less fertilizer than fields planted continuously with wheat, and produced just as much grain.”
The lentils behaved much like cover crops do. A common practice in organic farming, the lentil increased the nitrogen.
“Overall, the scientists estimated that for each kilogram of wheat they harvested, the soil removed up to a third of a kilogram of CO2 from the atmosphere,” explains Civil Eats. “That bodes well for the large swaths of the planet where Spring wheat is grown in semi-arid environments similar to the North American Great Plains, like China, India, and parts of South America.”
Does that mean we should all increase our intake of wheat? After all, it’s a grain that’s become increasingly less tolerated—from the rise in Celiac disease to other gluten sensitivities. But some experts think that those “sensitivities” aren’t as real as people think. In other words, if you’ve been avoiding wheat because you think it upsets your body, it may be more of a psychological reason than a digestive one.
Another benefit to wheat is that it’s not genetically modified like other major U.S. grown crops, soy and corn. The U.S. is also the largest producer of wheat in the world, so it’s a local food in that regard, unlike some of our other beloved commodities. Supporting American farmers is important to our economy and our food system. Of course, all wheat is not created equal. But it can be part of a healthy diet for humans and the planet.
Find Jill on Twitter @jillettinger
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Image: John Loo