This fascinating article about dirt re-evaluates traditional farming practices in light of new insights on soil science. According to soil scientist Rick Haney at the US Department of Agriculture’s Natural Resources Conservation Service- the issue is fertilizer. For decades, most American farmers have been relying on various chemical fertilizers to ensure the health and bounty of their crops- but it turns out that fertilizer might not be so necessary after all. Advances in soil testing have expanded the perspective on soil health, so that tests can now include the functions of microbial organisms present in the soil- not just the chemical compounds found in the soil itself.
“Our entire agriculture industry is based on chemical inputs, but soil is not a chemistry set,” Haney explains. “It’s a biological system. We’ve treated it like a chemistry set because the chemistry is easier to measure than the soil biology.”
In nature, of course, plants grow like mad without added synthetic fertilizer, thanks to a multimillion-year-old partnership with soil microorganisms. Plants pull carbon dioxide from the atmosphere through photosynthesis and create a carbon syrup. About 60 percent of this fuels the plant’s growth, with the remaining exuded through the roots to soil microorganisms, which trade mineral nutrients they’ve liberated from rocks, sand, silt, and clay—in other words, fertilizer—for their share of the carbon bounty. Haney insists that ag scientists are remiss if they don’t pay more attention to this natural partnership.
“I’ve had scientific colleagues tell me they raised 300 bushels of corn [per acre] with an application of fertilizer, and I ask how the control plots, the ones without the fertilizer, did,” Haney says. “They tell me 220 bushels of corn. How is that not the story? How is raising 220 bushels of corn without fertilizer not the story?” If the natural processes at work in even the tired soil of a test plot can produce 220 bushels of corn, he argues, the yields of farmers consciously building soil health can be much higher.