The following in an excerpt from Storm Lake by Art Cullen, published by Viking, an imprint of Penguin Publishing Group, a division of Penguin Random House, LLC. Copyright © 2018 by Art Cullen. Read an interview with Cullen here.
The greatest threat to Iowa, from Storm Lake to Des Moines, is not Islam or Mexicans hopping off a freight train if they don’t die trying. The greatest threat to Iowa—and, ultimately, a stable food supply in the United States—is its continued loss of soil. Rick Cruse, an agronomist at Iowa State, notes that wheat production already is falling every year in China because of soil deterioration. Extreme weather events wrought by warming make the task of keeping Iowa soil in place even harder.
Economist Harl recalls that in 1937 his family raised 40 bushels of corn per acre. In 2011 his southern Iowa farm produced 220 bushels of corn per acre. That corn sucked up a lot of fertilizer suspended in a lot of water. That pace cannot be sustained unless there is something to hold the water in place.
And there isn’t. Cruse will show you aerial photos of the Des Moines lobe—the corn capital of the world—where the precious topsoil depth has shrunk from fourteen inches to nothing in the span of a century. It starts on the knobs and spreads to the flat ground as the wind whips water across the bare black slate where you don’t see a tree for miles.
Soil erosion rates have amplified since the 1980s because of more extreme weather combined with less land in pastures and buffers and intensified row-crop production that packs much higher plant populations per acre.
Soil can hold water during drought, but if there is less soil in place, resiliency weakens. Cruse, who runs the Iowa Daily Erosion Project, tells us that our Iowa and Illinois prime cropland is floating downriver.
Cruse has been taking his analysis around the state trying to get people to listen: Climate change is upon us. The only way we can continue to reach optimum corn production in an increasingly hungry world is to maintain the soil base that the Good Lord left us when the plow arrived after 1850. We can’t do that the way we are farming—all out on virtually every acre.
Buena Vista County’s flat land is losing soil four times faster than nature can regenerate it. Iowa can regrow up to a half ton of soil per acre per year. Federal authorities say five tons per acre lost annually is “acceptable.” Such acceptable losses are common after a two-inch rain. We are losing soil way faster than we can grow it.
Cruse notes that corn potential is derived from genetics, man- agement, and water transpiration. You can get the best genetics and get plant populations as high as possible, but you can reach that crop’s potential only with adequate water. Topsoil, rich in organic matter, stores water for the corn plant. For every inch of topsoil you lose, corn production capacity is lost with it.
In the next twenty years world population is set to grow by up to 3 billion people, who will depend on less tillable land to feed them. We will need all the production capacity we can get. We lost 41 million acres of farmland to development from 1982 to 2017. Irrigated land provides 40 percent of the world’s food, and we are pumping our aquifers down. Given those daunting facts, it would seem an abomination to just dump that precious soil—which could feed a hungry world—into the river so it can choke the Louisiana bayou.
“Iowa had the world’s best soil. Louisiana has it now,” Cruse mused of our displaced treasure.
Demand for food and for better diets is increasing. Crop prices are on an average trend line up and will continue that trajectory, Cruse thinks, despite the downturn of recent years. The only incentive is for producers to produce in search of higher yields at higher prices, with a safety net called crop insurance that protects their adventurism. That will cause more water pollution and more soil loss, unless the federal government steps in and requires conservation practices. Discomfort causes change, says Iowa State economist Dave Swenson. Well-settled farmers are more comfortable than ever because of the safety nets and the genetic breakthroughs that defend against drought and pestilence, planted in an oil base that can be purchased.
The cost is not obvious, but it lurks below the surface.
Cruse said he has no doubt that crops are losing yield potential that genetics and technology cannot fully replace. Corn quality has been declining as measured by protein content from Iowa fields. Cruse points to the connection between soil health and human obesity—Latinos who live on a diet high in corn are trapped in a diabetes crisis, according to local health officials. Cruse relates that to higher starch and lower protein content in the corn kernel. Traces of that starchier corn kernel are in al- most every processed food and drink on the grocery shelves.
The increase in ethanol consumption brought on by the Renewable Fuels Standard—which made a lot of farmers rich over a three-year span—may mask the long-term implications of how it is destroying our land and eroding rural communities.
“We were living on a sugar high,” Swenson said of the spike in crop and land prices leading up to 2009 fueled by ethanol.
It gave us a rush to rip up more grass and get in on that seven-dollars-per-bushel corn for a fleeting time. But the damage was done, the soil gone. And now corn has crashed back to three dollars per bushel, prompting farmers to go after even more acres to get maximum revenue. The rule of modern agriculture: Spread your fixed costs over more acres.
“We’re moving down a one-way street,” Cruse said.
That black gold swirls in our lakes and rivers and eventually to the Gulf of Mexico. Those prairie potholes are the canaries in the coal mine. Lose the lakes and you won’t be growing corn for long. Not in Iowa, anyway. And we are losing them.