Illinois Facing Most Severe Erosion In Two Decades

Illinois is losing topsoil – the layer of surface dirt that’s rich with nutrients and vital for food production. And the problem of erosion on Illinois farms is serious: In 2015, roughly one-fifth of Illinois’s farmland lost more soil than it made.

Editor’s note: If you want to really dig in to soil loss, check out the annotated version on the reporter's website. If you want the quick and dirty, listen to the audio version, a Q and A with the reporter.

When retired Champaign County Resource Conservationist Bruce Stikkers first came to Central Illinois in the ‘70s, he remembers seeing mounds of mud in roadside ditches following the heavy spring rains. In the winter, dirt would blow like snow.

He says an older tilling technique involving what's called a Moldboard plow was the culprit. The plow would cut deep into the soil, loosening it so much that the elements could cart it off with ease.

“Now no one uses them. There is a lot less soil erosion than what there was, but we’re still not perfect by any means,” he says.

“Not perfect” may be putting it mildly. The most recent data from the Illinois Department of Agriculture shows roughly one-fifth of Illinois farmland is losing soil.

The immediate consequences of erosion include lower-yielding crops and damage to the environment. And the long-term consequences could be more severe, as the continued loss of soil over the next several decades could eventually convert farmland into infertile ground. Both soil conservationists, environmentalists and farmers agree something needs to be done to rein in erosion before it’s too late. But they disagree on what constitutes the best path forward.

Soil basics

Soil is considered by scientists to be a non-renewable resource, because although it can be created—from decaying plant material and the slow, geological breakdown of minerals—the process is extremely slow. Some scientists estimate it takes about 100 to 1,000 years to make an inch of top soil from these natural processes.

Illinois has some of the most fertile soil in the world, a result of thousands of years of year-round prairieland and the minerals left behind by prehistoric glaciers. But the introduction of modern agriculture techniques resulted in the replacement of prairie with farms that grow annual crops—leaving fields bare for much of the year.

This lack of a prairie “mat” coupled with tilling—the common practice of loosening the soil to enable roots to sprout more easily—has made soil vulnerable to harm by rain and wind. Hilly lands, prevalent in southern regions of Illinois, are most susceptible to losing soil as rain runs faster down slopes than flatter land, carrying more soil with it.

The amount of soil loss to date is stark, says Jennifer Filipiak, associate Midwest director at American Farmland Trust.

“Overall, we’ve lost about half of the organic matter that we had when we started plowing,” she says, referring to the portion of soil created from decaying plant matter. “In terms of tons of soil lost, that is a lot. It’s really a lot. I couldn’t even wrap my head around it.”

When a farm loses more soil than it’s made, it experiences what the agricultural industry refers to as “above tolerable soil loss.”

According to a recent survey, 7 percent of Illinois farmland has twice the amount of soil loss considered "above tolerable," the same as was the case in 1994. Twelve percent is between one and two times the tolerable soil loss level, which represents a 25 percent decrease since 1994, but still at the highest it has been since at least 2006.

The survey has been conducted by the Illinois Department of Agriculture every other year since 1994. It involves sending resource conservationists like Stikkers to check hundreds of transects, or survey points, through their windshields, and was started to track Illinois’ progress away from excessive soil loss.

Through public outreach and cost-share programs carried out by Soil and Water Conservation Districts – and time – the hope was erosion could be reined in without government regulation, Stikkers says.

For each point, resource conservationists determine how much residue is left on the field from harvest, and look through a spreadsheet to see how much erosion that residue level results in for the type of soil. It’s not a perfect survey—one study in Iowa found that a similar technique didn’t account for gully erosion, which under a new modeling method, resulted in as much as $1 billion in losses for Iowa’s agriculture.

Michelle Wander, a professor at the University of Illinois, says that since yields for conventional crops have skyrocketed with increased inputs, and genetic and mechanical improvements, the loss of yield from erosion has been “masked.”

“Back in the early 20th century, we were the first country to set a soil conservation agenda. We were losing too much, and we weren’t making it up with these improvements you’re seeing now,” she says. “But it’s still happening, and it’s really quite severe.”

Percentage of farms that lost more soil than was made in 2015

Why it matters

Department of Agriculture Soil Scientist Roger Windhorn says Illinois won’t be hitting bedrock anytime soon with the soil loss rates he sees. However, erosion does mean lower yields on farms that have it, and lower yields for farmers who inherit or buy the land for years down the road. That translates into less revenue for local governments, since property taxes for farmland are based on potential yield.

Erosion also leads to reduced water quality downstream. Phosphorus fertilizers cling to soil particles and make their way into water sources. The sediment often settles at the bottom of a waterway, and if it’s particularly shallow, or the sediment builds high enough, the sun can bake the phosphorus and cause an algal bloom. Many of these blooms make the water harmful for human consumption and recreation.

The sediment itself also reduces the amount of water a body of water can hold. The City of Decatur in central Illinois is in the process of a $90 million dredging project to increase the volume of their lake to keep it stable during droughts.

Craig Cox of the Environmental Working Group added that erosion needs to be reined in now because climate change is going to make erosion more severe. Winds in the Midwest are expected to pick up by 2 percent by the end of the century, and rainfall is expected to increase, bringing a projected 30 to 274 percent rise in erosion, according to one study.

Ironically, soil is one of humanity’s best chances to reduce emissions and slow climate change. Plants take in carbon dioxide and store it in the ground, making them what scientists call carbon sinks – but when a farmer tills, much of that carbon is released into the atmosphere. If every country in the world built-up its soil organic carbon by .4 percent each year, the world would lock-away 75% of the greenhouse gas annually. France has signed up for this goal, but so far the U.S. has not.

Layer one: funding for soil conservation has declined for 8 years

Soil erosion on medium-sloping farmland is inevitable, Windhorn says. That’s where a state soil conservation fund comes in. To keep soil on these fields, the farmers need costly structures, like terraces – mounds that go down the slope of a field to catch water.

Soil and Water Conservation Districts use money from the fund to build the structures, and farmers just have to pay a portion. Mike Rahe, manager of the state’s 97 Soil and Water Conservation Districts, says the funding for these has been on a steady decline on the state level. Federally, money has also plateaued for programs like the Conservation Reserve Program, which pays farmers a rent to keep highly erodible land out of production.

“Now that we're on the downside of that funding curve, we're not spending enough money to maintain that level of conservation, to maintain those practices that were installed before, because they don't last forever,” Rahe says, referring to terraces and other structures that lose effectiveness after about a decade.

With the drop in funding, farmers either have to spend more out of their pocket, or be put on a waiting list to get a structure built or rebuilt on their land, Rahe added.

Additionally, the drop in funding has led to a drop in personnel—by about 30 percent—so there are fewer trained staff available to give soil conservation advice to farmers.

Layer two: Environmentalists say not enough farmers are adopting soil conserving practices

There are options on the table for farmers to reduce erosion without having to dip into declining conservation funds. Some examples include:

• Cover crops: Planted after harvest, certain breeds of cover crops can deflect rain and lock soil up until a few weeks before planting starts.

• Tilling less or not at all: Tilling is a practice farmers use to mix the rain-deflecting stalks and leaves underground and loosen the soil to make it easier for the next crops’ roots to break-through. The transect survey found 44 percent of Illinois farmers still use conventional methods, meaning they pass over their field multiple times, making the soil appear black. This type of tilling leads to the most erosion.

• Tilling in the spring instead of the fall: Many farmers leave the stalks and leaves on the field over the fall, winter and most of spring, only tilling a few weeks before planting. This greatly reduces the time the bare field is exposed to the elements. The transect survey doesn’t track how many farmers do this, because it’s conducted in the spring.

• Reducing gullies: Gullies form when rain cuts channels in low spots in a field. They form after heavy rain. They can be reduced on relatively flat land by leaving all the residue over that part of the field. On steeper land, farmers will often just turn the gully into grass, which covers the soil year-round and catches soil particles before they can move off the field.

The problem that vice president of the Environmental Working Group Craig Cox sees: All of these options (aside from the more recent push for cover crops) have been on the table for more than 30 years, and still not enough farmers have adopted them.

Photo Credit: Austin Keating/Illinois Public Media

There are two schools of thought on the issue. One camp says that more time and education will rein in soil loss, and that’s been the narrative of the soil and water conservation districts. The other camp, the one that Cox is part of, says that regulation needs to happen.

One of the major success stories for the camp calling for increased education is that farmers have been able to decrease the percentage of fields that have gullies from 25 percent in 2002, to 12 percent in 2015. Cox goes a step further and says the government should mandate that those remaining gullies be seeded with soil-locking grasses.

Filipiak, who is working on a soil curriculum through a three-year National Resources Conservation Service grant, says she thinks more education is the solution. However, she’s putting a greater emphasis on reaching agricultural retailers, trusted consultants to many farmers, as opposed to just farmers, the major audience of the conservation districts.

Layer 3: Farmers of highly erodible fields aren’t being held accountable

Many farmers in Illinois have signed up for a federally subsidized insurance program, and in order to receive the benefits, they have to put together a conservation plan for any “highly erodible” cropland and follow it. It’s often a combination of structural fixes and the options laid out in the Layer 2 subhead.

Farmer Mark Donnell had to come up with a plan for one of the farms he operates outside of Fox Ridge State Park near Charleston. He says he would use the same practices even if the government didn’t require him to, simply because it’s good for the land.

“You’ve got to be good stewards of the ground,” he explains. “I’m just passing through, and somebody else is going to be taking over. It's always been my thought that I want to pass the ground on to the next generation as good as, if not better as, when I got it.”

While Donnell says he wouldn’t deviate from his conservation plan, other farmers do, and the compliance checks the United States Department of Agriculture conducts often fail to catch them. The USDA’s own Office of the Inspector General found that from 2011 through 2012, the Department could have saved millions of dollars if it started adequately enforcing its rules.

The department responded and said it would address the issue within a newly created Compliance Division. But Environmental Working Group Vice President Craig Cox pointed to several other accountability reports from years prior that listed the same problem that this most recent report found. While he said progress has been made between these reports, he called it slow.

“There's just a lot of reluctance to enforce the ineligibility for benefits,” Cox says, adding that recent Farm Bills have added loopholes for farmers as well.

“It used to be a great standard, and it could be again, but I think after 30 or 40 years, the purely monetary approach is just not standing up to the pressure we're putting on our landscape,” he says.