Growing a Revolution, page 14
Together we returned to the No-Till Center, and Boa introduced me to Kokor Yaa, a young farmer dressed in jeans, rubber boots, and a long-sleeved flannel shirt—an outfit I couldn’t imagine wearing in that heat. But she looked perfectly comfortable as she led us off on a trail into the fields. Crossing over a series of rolling hills and valleys, I saw no surface water, no streams. The trail reminded me of walking through jungle in the Philippines or Amazon—but here everything was planted.
After bushwacking through cover-cropped cornfields and cacao forest for what felt like a mile, we came to a well-defined footpath that took us through a several-year-old plantain field with bare ground. Boa said to no one in particular, “Who did this? Oh, boy, it looks naked.”
We arrived at Kokor’s field, a rectangle with peppers at one end and plantains at the other. She’s never used any pesticide, for the simple reason that she can’t afford any. Because she’d slashed and burned this field for more than a decade before going no-till, the ground was covered with plant residue but still contained a lot of charcoal in the soil. Why did she change her methods? Boa’s Sunday school opened her eyes. She likes no-till because “even if it doesn’t rain, the soil is moist.” That, and the time she saves. It’s a long walk to and from the small shop in town where she works after she tends her field.
On the way back, Boa moved through this food jungle with steady sureness. He looked at every patch of crop, asking aloud: Is the soil covered or naked? Is it moist or dry? Are the crops tall and green or short and yellow? As we stepped onto the road back in front of the No-Till Center, Boa told me that he’s pleased with what he saw. “This year has been very dry, a good test of no-till.”
By this time, I was drenched in sweat. Thankfully, Boa’s chief farmer brought out a bag of green coconuts and a cutlass. He swiftly trimmed off the outer coconut shell, then cut a window into the top and pried it open so that we could get to the refreshing water inside. I’d been sweating so much that Boa insisted that I have a second. I was in no condition to object.
YOU CAN’T EAT GOLD
Once I’d finally cooled down, Boa took me to see one more thing: the destruction of the fertile valley bottoms by mining activity in the neighboring district of Amansie West. As we drove away from Boa’s village, the country became a hilly land of red and green—red soil and houses, green forest and crops. But the farther we went from the No-Till Center, the more bare, plowed ground we passed, each naked plot lacking in discernable organic matter and topsoil, with just reddish subsoil exposed at the surface. In some of the villages, it seemed like every house had a little store, and tangles of sheep obstructed the streets. Soon it became clear that although sheep have the run of towns, mining companies have the run of the land.
Over the past decade, Boa told me, Chinese mining companies have moved in to dig for gold in the river gravels that form the valley bottoms. They sieve the gravel, take the gold, and cast the leftovers back into long windrowed piles of tailings. Entire valley bottoms have been torn up and turned over.
The physical disturbance has not only destroyed the soil, but the spoil piles leach toxic runoff. As we crossed a putrid, muddy stream, Boa recalled, “When I was young, the streams here were crystal-clear; now you can’t drink from them.” In the mining district, villagers who used to get their water from streams now have to buy it in plastic bags from trucks that deliver daily to their village.
What was once good farmland is now a spoil-pile moonscape. Originally, no one could own the valley bottoms; they were protected by village chiefs. But the mining companies offered a lot of money, and one chief after another decided to take the quick cash and allow the destruction of the land and water. According to Boa, this style of shortsighted mining is starting to happen all over Ghana. He worries that governments across Africa are so hungry for investors, they don’t always care what they do. “The valleys are the most fertile lands. This was good land. This is so sad. The death of the land.”
The next morning before I had to leave to catch my flight, Boa and I sat around an orange plastic table with matching chairs on the upstairs veranda of the No-Till Farmers House. He smiled and spoke slowly as I wrote quickly, struggling to keep up in my attempt to take down his parting words. From our perch in Amanchia’s only two-story building, we could see a panorama of the village, its mud-brick houses and its inhabitants walking by, balancing loads on their heads, from flip-flops to fruit and chainsaws.
As he spoke, Boa’s eyes shone with evangelical passion. He is like a prophet of no-till in Ghana, trying to lead his people through several agricultural revolutions in a single generation, to go straight from slash-and-burn to conservation agriculture.
I asked if conservation agriculture can feed Africa, and Boa quickly replied. “The blunt answer is yes; we will especially need it as climate change continues to stress food production. Africa has traditionally been fed by small farms. If we combine no-till with appropriate crops and systems, I don’t see why we can’t continue to do that.”
People have been coming to this center from all over Africa to learn how. The productivity of subsistence farms in the continent is low, and it’s been declining in recent decades as fallow land isn’t available and soil degradation is widespread from continuous cropping with traditional methods. There is substantial interest in whether changing high-disturbance slash-and-burn practices to low-disturbance methods using cover crops, intercropping, and crop rotation can push progress toward sustainable development.
Boa sees low input costs as central to making conservation agriculture an effective way to address rural hunger and poverty among smallholders in Africa. He’d shown me how the same principles that transformed South Dakota can increase, and in some cases more than double, harvests for subsistence farmers—all without expensive irrigation or planting equipment and with minimal expense for inputs like fertilizer and herbicides.
Yet there is controversy over the potential for conservation agriculture to feed Africa, as reviews of no-till and conservation agriculture have come to conflicting conclusions. Some studies have reported that conservation agriculture required substantially more inputs or produced lower yields. I suspect that part of this is again due to variability in how conservation agriculture practices are defined and implemented. A 2014 study that reviewed available literature came to the conclusion that few studies had evaluated the effectiveness and cost of conservation agriculture when all three of its central principles were adopted.
One that did, a meta-analysis of sixty-one studies of sites across sub-Saharan Africa, found that increased crop yields under conservation agriculture depended on, again, adoption of all three aspects of conservation agriculture—no tillage, cover crops, and complex crop rotation. Such comparisons are complicated, however, by the reality that even if the principles are universal, the specific practices that work best will vary regionally and with farm-specific contexts.
Like Rattan Lal, Kofi Boa bemoans the wide range of practices called no-till. Why, he asks, would anyone even talk about, let alone do or study, bare-ground no-till? It just makes no sense when “bare soil is worse than tillage.”
There is no question that soil erosion must first be curtailed before soil fertility can be built up to sustain higher yields with fewer inputs. In the late 1970s, experiments in northern Ghana found about a twentyfold difference in erosion rates between bare and mulched fields. A more recent study of conservation agriculture in Zimbabwe found that coupling the use of organic matter as soil cover with integration of legumes into crop rotations not only reduced erosion, but helped reverse declining soil fertility and increased soil organic matter. Average corn yields under conservation agriculture were consistently higher, up to double those of nonconservation agriculture fields. And a long-term field trial in Zambia reported a 9 percent increase in soil carbon content in conservation agriculture fields, while there was a 7 percent decrease in neighboring conventionally tilled fields. In rural Mali, the combination of conservation agriculture with limited fertilizer use, or microdosing, provided short-term yield benefits combined with longer-term building of soil quality and soil organic matter. The takeaway from these studies seems clear: here conservation agriculture builds soil, and conventional agriculture degrades it.
A number of studies in sub-Saharan Africa have reported better economic returns for conservation agriculture than for traditional practices. Even when similar or higher yields are obtained, there can be significant savings in labor and time. For example, a three-year study of twenty-four farms in Malawi found that conservation agriculture plots with intercropped maize and pigeon peas (Cajanus cajan) produced a third higher maize yields after the first year, in which there was no difference. It also took farmers just three-quarters of the time to manage, and was twice as profitable as conventionally tilled maize. The soils on these farms had less than 1 percent organic matter, a value considered a minimum for maintaining crop production in the region. The study concluded that agronomic practices that increase soil organic matter were critically needed.
In another review of studies of reduced-tillage and no-till practices across Africa, the authors found that mulching was the key to improving soil properties and increasing crop yields. And a curious experiment in northern Burkina Faso found that mulching previously degraded soil attracted termites that devoured the mulch, breaking it down and thereby recycling nutrients and helping restore fertility to the land. The researchers applied several tons per hectare of dry straw and shrub mulch to completely bare and crusted soil, which had been referred to by local farmers as zipella, or “dead soils.” Soon termite burrows perforated the surface crust and allowed water to once again sink into the ground instead of running off.
Only a small number of smallholder farmers in sub-Saharan Africa have adopted full-on low-input conservation agriculture like what Kofi Boa teaches. A key limitation to expanding the adoption of cover-cropping systems in Africa is the availability of cover-crop seeds suited for African conditions. Boa said that farmers constantly ask him for cover crop seeds to help restore land they say has “spoiled” and is no longer fertile. They’ve learned what cover crops can do, but where can they get seeds? It looks like they’ll soon have a source. Howard Buffett’s foundation has converted parts of his farm in South Africa to produce high-quality, low-cost cover-crop seeds for distribution across Africa.
When I asked about other obstacles to broader adoption of conservation agriculture in Africa, Boa rattled off a short but daunting list: tradition, lack of political support, bad policies, and the difficulty of gathering and disseminating knowledge. African governments and foreign aid programs tend to focus on input-intensive approaches behind the get-big-or-get-out philosophy that transformed American agriculture in the late twentieth century. While the approach Boa advocates makes short-term economic sense for subsistence farmers, implementing it involves a change in thinking, rather than using products made by the companies that dominate the global business of agriculture.
This thought lingered with me as we drove to the airport, past small roadside stalls selling old-school treadle Singer sewing machines and racks of chickens in cages, a woman carrying a stack of ten egg boxes—sixty dozen eggs—balanced on her head, and a wrecking yard assembling rainbow Frankenstein taxis, each panel a different color. As I readied myself to leave Africa, I couldn’t help but think that the way for aid organizations and philanthropists to have lasting impact there is not through encouraging the “more on” approach, but through practices like Boa preaches. And, as he’s shown, the way to do this is to use demonstration farms to bridge the divide between research and local experience, between science and practice, to build a foundation of knowledge relevant to smallholders.
Despite the huge differences in soils, climate, and farming practices, the same guiding principles worked in both South Dakota and Ghana. Dwayne Beck patterns his practices on nutrient cycling through semiarid grasslands. Kofi Boa patterns his on nutrient cycling through tropical forest. Though specific practices differ depending on the situation of the farmer, I was starting to think that soil-building farming could be done around the world.
Both Dwayne Beck and Kofi Boa use herbicides and fertilizers, albeit sparingly. But can no-till work in conjuction with organic farming at scale? Can expanded cover crop and legume cultivation also improve organic methods? To explore these questions, I decided to visit the longest-running test of organic no-till farming, near Kutztown, Pennsylvania.
8
THE ORGANIC DILEMMA
If herbicides are so good, how come we still have weeds?
—Gabe Brown
People tend to assume that organic farming and sustainability go hand in hand. But that’s not necessarily the case—and it hasn’t been for most of history. While going organic has some big advantages, even today most organic farmers still rely on the plow—the chief culprit in this story. Why? Because it provides cheap, reliable weed suppression. Yet, as we know, it’s not the only option, nor are herbicides always a better alternative.
As far back as 1938, USDA agronomist Clyde Leighty wrote that “Rotation of crops . . . is the most effective means yet devised for keeping land free of weeds.”19 He suggested that the best defense against weeds was a cover of beneficial plants, grown to outcompete weeds and provide green manure.
Leighty also knew that crop rotation boosted harvests. “There are numerous cases on record to show the advantageous effects of rotating crops on yields and quality . . . the ravages of insect pests and of plant diseases are reduced to a minimum in a crop-rotation system . . .”20 To back up his claim, he presented data from a thirty-year field trial at the Missouri Agricultural Experiment Station, which showed that a four-year rotation of corn, oats, wheat, and clover increased yields by two-thirds to more than double those from monocultures.
Farmers had known about using cover crops to enhance soil fertility and bolster crop yields for centuries. But these practices lost their luster after the Second World War, as plentiful supplies of cheap chemical fertilizers offered comparable boosts in yield and allowed farmers to specialize in particular commodity crops and eliminate all the messy bother of animal husbandry. In short order, agriculture came to rely on chemical fertilizers to support high-yielding monocultures. Using cover cropping and crop rotations to maintain or build fertility and suppress weeds didn’t sound like progress when fertilizers and herbicides proved cheap, easy, and effective—at least in the short run.
That, however, wasn’t the only factor at play. Chemical manufacturers had influential allies in governments interested in supporting fertilizer factories that could convert back to munitions production on short notice.21 While not everyone jumped on the agrochemical bandwagon, increasingly specialized academic, industry, and agency researchers tended to dismiss organic farming as a throwback to prescientific days. By the 1950s, the USDA had gone all out to champion agrochemical farming.
No-till farming became more attractive after the advent of herbicides that offered a simple, practical alternative for weed control. Interest ramped up even more with the introduction of crops genetically engineered to tolerate the herbicide glyphosate, which kills nongenetically modified plants by disrupting a basic physiological process. The effectiveness of glyphosate gave its manufacturer, Monsanto, a huge advantage in the herbicide market and a monopoly on patented seeds for glyphosate-resistant crops. Conventional farmers loved glyphosate, even if using it didn’t appreciably improve per-acre harvests. They hated weeds and it killed them really well, offering easy, efficient weed control without plowing—at least at first. This, in turn, helped drive widespread adoption of genetically modified corn and soy.
The first herbicide-resistant weed surfaced in 1970, an atrazine-resistant groundsel. Six years later, Monsanto registered glyphosate for broad-spectrum weed control. The first glyphosate-resistant weeds, Wimmera ryegrass (Lolium rigidum), were reported in Australia in 1996—the year that glyphosate-tolerant crops were first introduced. By 2014, almost two dozen weed species with glyphosate-resistance were reported in the United States. Worldwide, a total of 432 different types of weeds were resistant to various herbicides. Naturally, this renewed interest in whether all those herbicides were really necessary after all. Could no-till be done organically, or did one have to choose between herbicides and the plow?
There’s no better place to ask this question than at the Rodale Institute, a 333-acre farm near Kutztown, Pennsylvania. The institute’s namesake, Jerome Rodale, was one of the first American advocates for organic agriculture. The sickly son of a Jewish New York City grocer, Rodale had built a successful manufacturing business, but in 1930 he decided to move his family to a farm in Emmaus, Pennsylvania.
When he asked university scientists what he should do with his newly purchased 70 acres, they recommended using chemical fertilizers and pesticides. This didn’t strike Rodale as particularly good advice, given the fact he’d left the city in the first place so his kids could have a healthier environment to grow up in. After reading Sir Albert Howard’s ideas about the relationship between soil health and human health, Rodale linked the word “organic” with agriculture and started an experimental organic farm in 1940. Two years later, he started Organic Gardening and Farming magazine (now called Rodale’s Organic Life). Publishing books and magazines about health-related issues made Rodale famous, and he became a prominent advocate for healthy living and organic farming using cover crops, crop rotation, and manure. Until, that is, he died of a heart attack on the set of The Dick Cavett Show in 1971. That year, Rodale’s son Robert purchased the Kutztown farm.
I’d seen Jeff Moyer, the institute’s farm manager (and now executive director), speak at a conference about how to manage cover crops without herbicides—a practical organic alternative for no-till weed control. Had he solved the puzzle of organic no-till? This is what I wanted to find out as I drove through Pennsylvania’s verdant rolling hills, sweating again on a muggy July day a week after returning from Africa.
