One Weird Trick to Fix Farms Forever
Does David Brandt hold the secret for turning industrial agriculture from global-warming problem to carbon solution?by Tom Philpott, Mother Jones, September 9, 2013
Brandt farms 1,200 acres in the central Ohio village of Carroll, pop. 524. This is the domain of industrial-scale agriculture—a vast expanse of corn and soybean fields broken up only by the sprawl creeping in from Columbus. Brandt, 66, raised his kids on this farm after taking it over from his grandfather. Yet he sounds not so much like a subject of King Corn as, say, one of the organics geeks I work with on my own farm in North Carolina. In his g-droppin' Midwestern monotone, he's telling me about his cover crops—fall plantings that blanket the ground in winter and are allowed to rot in place come spring, a practice as eyebrow-raising in corn country as holding a naked yoga class in the pasture. The plot I can see looks just about identical to the carpet of corn that stretches from eastern Ohio to western Nebraska. But last winter it would have looked very different: While the neighbors' fields lay fallow, Brandt's teemed with a mix of as many as 14 different plant species.
"Our cover crops work together like a community—you have several people helping instead of one, and if one slows down, the others kind of pick it up," he says. "We're trying to mimic Mother Nature." Cover crops have helped Brandt slash his use of synthetic fertilizers and herbicides. Half of his corn and soy crop is flourishing without any of either; the other half has gotten much lower applications of those pricey additives than what crop consultants around here recommend.
But Brandt's not trying to go organic—he prefers the flexibility of being able to use conventional inputs in a pinch. He refuses, however, to compromise on one thing: tilling. Brandt never, ever tills his soil. Ripping the soil up with steel blades creates a nice, clean, weed-free bed for seeds, but it also disturbs soil microbiota and leaves dirt vulnerable to erosion. The promise of no-till, cover-crop farming is that it not only can reduce agrichemical use, but also help keep the heartland churning out food—even as extreme weather events like drought and floods become ever more common.
Those are big promises, but standing in the shade of Brandt's barn this June morning, I hear a commotion in the nearby warehouse where he stores his cover-crop seeds. Turns out that I'm not the only one visiting Brandt's farm. The Natural Resources Conservation Service (NRCS)—a branch of the US Department of Agriculture (USDA) that grew from Dust Bowl-era efforts to preserve soil—is holding a training for its agents on how to talk to farmers about cover crops and their relationship to soil.
Inside the warehouse, where 50-pound bags of cover-crop seeds line one wall, three dozen NRCS managers and agents, from as far away as Maine and Hawaii, are gathered along tables facing a projection screen. Brandt takes his place in front of the crowd. Presenting slides of fields flush with a combination of cover crops including hairy vetch, rye, and radishes, he becomes animated. We listen raptly and nod approvingly. It feels like a revival meeting.
"We want diversity," Brandt thunders. "We want colonization!"—that is, to plant the cover in such a way that little to no ground remains exposed. While the cash crop brings in money and feeds people, he tells the agents, the off-season cover crops feed the soil and the hidden universe of microbes within it, doing much of the work done by chemicals on conventional farms. And the more diverse the mix of cover crops, the better the whole system works. Brandt points to the heavy, mechanically operated door at the back of the warehouse, and then motions to us in the crowd. "If we decide to lift that big door out there, we could do it," he says. "If I try, it's going to smash me."
For the agency, whose mission is building soil health, Brandt has emerged as a kind of rock star. He's a "step ahead of the game," says Mark Scarpitti, the NRCS state agronomist for Ohio, who helped organize the training. "He's a combination researcher, cheerleader, and promoter. He's a good old boy, and producers relate to him." Later, I find that the agency's website has recently dubbed Brandt the "Obi-Wan Kenobi of soil."
Soon, we all file outside and walk past the Brandt family's four-acre garden. Chickens are pecking about freely, bawk-bawk-bawking and getting underfoot. In an open barn nearby, a few cows munch lackadaisically. I see pigs rooting around in another open barn 30 or so yards away and start to wonder if I haven't stumbled into a time warp, to the place where they shot the farm scenes in The Wizard of Oz. As if to confirm it, a cow emits a plaintive moo. Brandt's livestock are something of a hobby, "freezer meat" for his family and neighbors, but as we peer around the barns we see the edges of his real operation: a pastiche of fields stretching to the horizon.
Before we can get our hands in the dirt, Brandt wants to show us his farm equipment: the rolling contraption he drags behind his tractor to kill cover crops ahead of the spring and the shiny, fire-engine-red device he uses to drill corn and soy seeds through the dead cover crops directly into the soil. As some NRCS gearheads pepper him with questions about the tools, he beams with pride.
Finally, we all file onto an old bus for a drive around the fields. An ag nerd among professional soil geeks, I feel like I'm back in elementary school on the coolest field trip ever. An almost giddy mood pervades the bus as Brandt steers us to the side of a rural road that divides two cornfields: one of his and one of his neighbor's.
We start in Brandt's field, where we encounter waist-high, deep-green corn plants basking in the afternoon heat. A mat of old leaves and stems covers the soil — remnants of the winter cover crops that have kept the field devoid of weeds. At Brandt's urging, we scour the ground for what he calls "haystacks" — little clusters of dead, straw-like plant residue bunched up by earthworms. Sure enough, the stacks are everywhere. Brandt scoops one up, along with a fistful of black dirt. "Look there — and there," he says, pointing into the dirt at pinkie-size wriggling earthworms. "And there go some babies," he adds, indicating a few so tiny they could curl up on your fingernail.
Then he directs our gaze onto the ground where he just scooped the sample. He points out a pencil-size hole going deep into the soil — a kind of worm thruway that invites water to stream down. I don't think I'm the only one gaping in awe, thinking of the thousands of miniature haystacks around me, each with its cadre of worms and its hole into the earth. I look around to find several NRCS people holding their own little clump of dirt, oohing and ahhing at the sight.
Then we cross the street to the neighbor's field. Here, the corn plants look similar to Brandt's, if a little more scraggly, but the soil couldn't be more different. The ground, unmarked by haystacks and mostly bare of plant residue altogether, seems seized up into a moist, muddy crust, but the dirt just below the surface is almost dry. Brandt points to a pattern of ruts in the ground, cut by water that failed to absorb and gushed away. Brandt's land managed to trap the previous night's rain for whatever the summer brings. His neighbor's lost not just the precious water, but untold chemical inputs that it carried away.
Aside from his fondness for WORMS, there are three things that set Brandt's practices apart from those of his neighbors — and of most American farmers. The first is his dedication to off-season cover crops, which are used on just 1 percent of US farmland each year.
The second involves his hostility to tilling — he sold his tillage equipment in 1971. That has become somewhat more common with the rise of corn and soy varieties genetically engineered for herbicide resistance, which has allowed farmers to use chemicals instead of the plow to control weeds. But most, the NRCS's Scarpitti says, use "rotational tillage" — they till in some years but not others, thus losing any long-term soil-building benefit.
Finally, and most simply, Brandt adds wheat to the ubiquitous corn-soy rotation favored by his peers throughout the Corn Belt. Bringing in a third crop disrupts weed and pest patterns, and a 2012 Iowa State University study found that by doing so, farmers can dramatically cut down on herbicide and other agri-chemical use.
The downsides of the kind of agriculture that holds sway in the heartland — devoting large swaths of land to monocultures of just two crops, regularly tilling the soil, and leaving the ground fallow over winter — are by now well known: ever-increasing loads of pesticides and titanic annual additions of synthetic and mined fertilizers, much of which ends up fouling drinking water and feeding algae-smothered aquatic "dead zones" from Lake Erie to the Gulf of Mexico.
But perhaps the most ominous long-term trend in the Corn Belt is what's known as peak soil: The Midwest still boasts one of the greatest stores of topsoil on Earth. Left mostly unfarmed for millennia, it was enriched by interactions between carbon-sucking prairie grasses and mobs of grass-chomping ruminants. But since settlers first started working the land in the 1800s, we've been squandering that treasure. Iowa, for example, has lost fully one-half — and counting — of its topsoil, on average, since the prairie came under the plow. According to University of Washington soil scientist David Montgomery, author of Dirt: The Erosion of Civilizations, it takes between 700 and 1,500 years to generate an inch of topsoil under natural conditions. Cornell agricultural scientist David Pimentel reckons that "90 percent of US cropland now is losing soil faster than its sustainable replacement rate." Soil, as Americans learned in the Dust Bowl, is not a renewable resource, at least on the scale of human lifetimes.
Then there's climate change itself. Under natural conditions — think forests or grasslands — soil acts as a sponge for carbon dioxide, sucking it in through plant respiration and storing a little more each year than is lost to oxidation in the process of rotting. But under current farming practices, US farmland only acts as what the USDA has deemed a "modest carbon sink" — sequestering 4 million metric tons of carbon annually, a tiny fraction of total US greenhouse gas emissions.
The good news, says eminent soil scientist Rattan Lal of Ohio State University, is that if all US farms adopted Brandt-style agriculture, they could suck down as much as 25 times more carbon than they currently are—equivalent to taking nearly 10% of the US car fleet off the road. (Lal, a member of the Nobel-winning International Panel on Climate Change, is so impressed with Brandt's methods that he brought a group of 20 Australian farmers on a pilgrimage to Carroll two years ago, he tells me.)
Building up organic matter is critical to keeping the heartland humming as the climate heats up. The severe drought that parched the Corn Belt last year — as well as the floods that have roared through in recent years — are a harbinger of what the 2013 National Climate Assessment calls a "rising incidence of weather extremes" that will have "increasingly negative impacts" on crop yields in the coming decades.
As Ohio State soil scientist Rafiq Islam explains, Brandt's legume cover crops, which trap nitrogen from the air and store it in nodules at their roots, allow him to grow nitrogen right on his farm, rather than importing it in the form of synthetic fertilizer. And the "complex biological systems" created by cover crops marginalize crop-chomping bugs and disease-causing organisms like molds — meaning fewer insecticides and fungicides.