The 10 warmest years on record, including 2012, all fell within the past 15 years. Climate change is happening, now, and the breadbasket state of Kansas is a good example of its likely effect on farming. On 1/16, the UDSA declared much of the wheat belt a disaster area because of the drought’s effect on the crop.
Since the Great Depression, US farm policy has been governed by 5-year plans, or farm bills. They are government-funded incentive programs and they shape the agricultural landscape. Indeed, since World War II, farmers in the US heartland have been incentivized on producing as much of a few chosen crops, like corn, soy, and wheat (very chemical-intensive), as possible. Mono-crop farming has blanketed the Midwest and is now beginning to show serious vulnerability to climate change.
Before farm bill season begins, the House and Senate ag committees and USDA decision makers need to understand this: by diversifying away from the old corn-soy-corn rotation and adding off-season, nitrogen-fixing cover crops to the mix, farmers will dramatically decrease reliance on chemical fertilizers and toxic herbicides, while maintaining yields. The 2012 Leopold Center for Sustainable Agriculture’s report shows how rotations enrich the soil with plant-available nitrogen and organic carbon, break disease and weed cycles, and diminish erosion by putting living roots and cover on the ground. Rotations also protect nearby waterways from pollution and reduce the risk of creating herbicide-resistant weeds. Benefits build over time for farmers with lower herbicide needs (reducing herbicide-related freshwater toxicity) and energy need.
What does this have to do with drought? By planting off-season legume cover crops, farmers do not just add nitrogen to soil: legumes have the magical property of grabbing nitrogen from the air and depositing it in their roots, thus fertilizing soil. All the roots they leave behind also add organic matter to soil, which helps it hold water, a precious characteristic when water runs short.
With conventional farming techniques (extensive tillage, low crop diversity, no cover crops, livestock kept out all-season long on overgrazed pastures), the soil is so compacted that little water can make its way beneath the surface. There is very little soil organic matter, which drives the entire soil food web. Prairie have unbroken soils hence little opportunity to cook up its own fertility via the exchange of nutrients. Hence farmers’ high dependency on applications of petroleum-based fertilizers.
Only cover-cropping, first tried a decade or so ago, and with it farmers turning their soil into their key investment (not the next crop squeezed out of it) can produce notable changes. Yet, federal farm policy encourages the exact opposite path and pushes farmers to plant as much as possible of the same and then subsidizes crop insurance against losses, giving them no incentive to build organic matter in soil.
The takeaway for policymakers is simple: Quit rewarding farmers for maximizing yield and start paying them to build organic matter in their soil. One exceedingly simple measure would be to pay farmers to plant cover crops. The result would be an ag system that is much more ready for the long, hot, dry spell that is coming.