By Julia Gerlach, Soil Health Specialist, Conservation Technology Information CenterDirt cheap. Treat like dirt. Drag through the dirt.
We’ve all heard – and probably used – these and other negative idioms. They are, after all, old as dirt. Sorry, it couldn’t be helped.
But truly, it’s no way to talk about agriculture’s most precious commodity – the soil.
Dust in the wind
It’s easy to think of the soil as an infinite resource, that it will always be there. But the fact is many prior civilizations have met their peril as a result of destroying their soils. David Montgomery wrote about this in Dirt: The Erosion of Civilizations, as did Walter Lowdermilk in his 1953 booklet Conquest of the Land Through 7,000 Years. Both books trace the destruction and erosion of soil that has gone hand-in-hand with the fall of civilizations throughout the ages.In the Dakota Lakes Research Farm (DLRF) Annual Progress Report 2022, former DLRF manager and no-till pioneer Dwayne Beck reminds readers that the westward expansion of the United States that occurred with the Louisiana Purchase was in many ways a result of soil degradation that began with the birth of agriculture.“When hunter-gatherer societies were replaced with agriculture, there was also a switch from using contemporary nutrients to grow plants to a system that was based on accelerating the natural release of nutrients from the soil through the use of tillage and/or fire,” he writes. “Even in the early phases this led to widespread degradation of soils and ecosystems.”He goes on to explain that the colonization of Africa, Australia and the western hemisphere was “an effort to find land that had not been degraded to support population growth.”The degradation of the soil continued to follow each new society as settlers brought to the new lands the very cultivation methods that had created the erosion problems they were seeking to escape.Beck goes on to explain that founding fathers George Washington, Alexander Hamilton and Thomas Jefferson expressed concern about soil degradation on the eastern seaboard in their correspondence in the 1790s.“They felt better husbandry was required to prevent further damage,” Beck writes. “If improvement was not made, then it would be necessary to look westward for new lands. The Louisiana Purchase occurred seven years later. In just over one hundred years, the Dust Bowl impacted the newly purchased land because techniques had not changed.”While the dust storms of the Dirty Thirties may seem like a thing of the past, intense storms in the last year or so have kicked up walls of dirt that traveled hundreds of miles, depositing South Dakota soil far and wide. On May 13, 2022, social media was full of images of a massive dust storm as it passed through the eastern part of South Dakota and into Minnesota. That storm caused two deaths and millions of dollars in damage. On May 1, 2023, a massive accident due to a dust storm in Illinois involving 30 commercial trucks and more than 50 passenger vehicles resulted in 7 deaths and 30 hospitalizations.
A windstorm kicked up a massive cloud of soil and dust that traveled through the eastern part of South Dakota and into Minnesota in May 2022. Experts estimate the storm stripped away 1-2 mm of soil from farms across the state. Photo by Christian Begeman.
It's convenient to think of recent windstorms as freak events and to imagine that aggregated soil loss is not that severe. But a 2022 study that appeared in the journal AGU Advances found historical soil erosion rates averaging nearly 2 mm per year, which is almost double the rate considered “tolerable” by the United States Department of Agriculture (USDA).If a 2 mm loss equates to 12 tons per acre, and South Dakota has 41 million acres of farmland, that’s a LOT of topsoil being whisked away every year. And besides the physical soil loss, this erosion also represents a loss of applied nutrients, reduced soil organic matter and a loss of soil moisture, all of which costs farmers money.The good news is that management practices can help stave off erosion and protect the soil during big wind and rain events. Planting cover crops after harvest, for instance, helps keep soil in place, adds organic matter and improves water-holding capacity in the soil.According to Operational Tillage Information System (OpTIS) data, only about 3% of farmland acres in South Dakota were planted with cover crops in 2021, the most recent year for which data is available. This lags behind the average 5.9% of acres planted with covers nationwide that year.While the benefits of using cover crops are well established and widely understood, implementation remains challenging in the state where the growing season averages just 135 days between the last and first frost, and precipitation swings wildly from too much to not enough.Furthermore, many farmers are reluctant to plant cover crops because of a perception that they are a financial risk, either in terms of negatively impacting yield on the following cash crop or from the expense of the seed itself and related management – or both.Results from a recent study by the Soil Health Institute (SHI), however, suggest that adopting cover crops and other soil health practices can help farmers improve profitability in the long run.In a press release about the study, Dr. Wayne Honeycutt, President and CEO of SHI, said, “We know practices like cover crops and no-till benefit the environment by storing soil carbon, reducing greenhouse gas emissions and improving water quality. However, investing in soil health is also a business decision. This project provides farmers with the economic information they need to feel confident when making that decision.”The study included in-depth interviews with 30 farmers across 20 states with an established history of successful implementation of a wide range of soil health management systems including cover crops, no-till, planting green, rotational grazing and more. SHI designed the interviews to “learn about farmers’ experiences with adopting those systems and to evaluate their economics by comparing the costs and benefits before and after practice adoption,” the press release stated.The study found that 29 of the 30 farms increased net farm income by an average of $65 per acre through a combination of reduced costs and increased yields in the cash crop parts of the rotation. Farmers also reported decreased soil erosion and compaction, earlier access to fields in wet years and increased resilience to extreme weather.Doug Sieck, a no-tiller from Selby, S.D., who started adding cover crops to his corn-soybean-wheat rotation in fall 2006, can relate. While today he is a vocal advocate for cover crops and caring for the soil, he says his interest in soil health didn’t begin altruistically.“My original motivation really wasn’t the health of the soil,” he says. “It was financial.”Sieck says he was inspired by Bismarck-area no-tiller Gabe Brown, whose farm was part of a South Dakota Crop Improvement bus tour that year. While standing in a chest-high warm-season cover crop, Brown explained that the cover crops were boosting his profits by allowing him to cut back on the use of fertilizers and pesticides. Intrigued, Sieck decided to seed about 30 acres to a mix of winter triticale and hairy vetch after soybean harvest.“I also threw in some turnips or radishes just for fun,” he says. “I planted it to cut for hay the next year, and it worked out really well. I got a lot of bulk off of it.”Sieck, who considers himself a cattleman first and a farmer second, could see the potential for using cover crops to feed his livestock while also benefiting the soil.
Doug Sieck of Selby, S.D., sets out temporary polywire fencing to manage which cover crop fields his cows have access to. Photo courtesy of Doug Sieck.