Biomimicry Page 5
Though they don’t know all the particulars, Piper thinks a typical recipe may work like this: You throw in the recommended mix of species (more than you need), making sure that all important plant groups are represented. Then you sit back and watch the trajectory unfold. The trajectory might take five years, say, but you would be rewarded with a complex, persistent system.
“Right now, for instance, we’re seeing a flush of annual weeds the first and second year. The fields look awful at first, like a total failure, but the perennial seeds are in there and by the second or third year, they just go whoosh and come into their own. Somehow, the environment filters out what works from what doesn’t work, so you are left with the most stable combination. We’re studying how this happens, and what steps we might take to help it to happen.” As their plots mature, The Land Institute will be experimenting with various management techniques to favor perennial grains and to get the community to gel. The resultant recipe might include a recommendation to burn in year two, mow in year three, or graze livestock in year four. They’ll also be thinking about the equipment that will be needed to harvest the different crops at different times of year.
“Farming with a crowd of perennials is going to be different,” says Piper. “It’ll be more like forestry in that you have to wait a while to get to a harvestable stage. Also as with forestry, you can’t just start over each year. You can’t decide to grow another crop because pests are bad or the weather doesn’t cooperate. Instead, you’ll have to plan up front for multiyear conditions—weather, markets, et cetera. Your best hedge against disaster is going to be variety, just as the prairie teaches—lots of paints in your palette so that no matter what the conditions, some species will still flourish.”
Besides getting the domestic prairie to take, visionaries at The Land also want it to fulfill its promise agriculturally. It has to compete reasonably well with what farmers are now growing. The final three questions that occupy Piper and company have to do with the polyculture performance from that pragmatic point of view.
Can the polyculture yields stay even with or actually overyield those of monocultures?
Overyielding is the phenomenon by which a crop yields more per unit acre when it’s growing in a polyculture than when it’s in a monoculture. Turns out that plants grown next to different but complementary neighbors don’t have to compete the way they do when grown next to an identical plant. They’re not jostling root elbows for the water in a particular level, for instance. Nor are they competing for the same plane of sunshine. As a result, the members of a diverse community are actually capturing more resources (and yielding more) than they would under constant same-species competition.
The literature is replete with examples of overyielding when complementary annuals such as maize, beans, and squash are planted together. Piper’s charge was to show that overyielding could happen with perennials as well. “Sure enough, we’re seeing it,” he says, letting a grin escape with this news. “Nineteen ninety-five was the fifth year of a study of polycultures of eastern gamagrass, wildrye, and Illinois bundleflower. When compared with their performances in monoculture, plants in mixtures have consistently overyielded.”
Can the polyculture defend itself against insects, pests, and weeds?
Studies at The Land are showing that when plants are grown in bicultures and tricultures, they’re better able to fight off insects and diseases than when they’re grown in monocultures. It makes sense if you think about it. Plants defend themselves against insects with chemical “locks,” and at most, an insect carries only one or two “keys” to the plants it is adapted to eat. An insect that finds itself in a field of nothing but its target plant is like a burglar with the key to every house in the neighborhood. In a polyculture, where all the locks are different, finding food is more of a chore. A mixed neighborhood is equally frustrating for diseases that specialize in one plant. A fungus may fester on an individual, but when it releases its spores, the leaves of invulnerable plants act as a flypaper, bringing the fungal rampage to a halt. That’s why, although pests exist in prairie polycultures, you don’t see the runaway decimation that you see in monocultures. Invasions are contained.
Just as with overyielding, most of the experimental evidence for resistance comes from studies on annual plants in polycultures. In 1983, Cornell biologists Steve Risch, Dave Andow, and Miguel Altieri reviewed 150 such studies and found that 53 percent of the insect pest species were less abundant in annual polycultures than in annual monocultures. Similarly, Australian ecologist Jeremy Burdon summarized 100 studies of two-component mixtures and found that there were always fewer diseased plants in the polyculture. So far, the same seems to hold true for the perennial polycultures planted at The Land. “In the third year of testing,” says Piper, “we had a sudden buildup of beetles on bundleflower. But only in the monocultures. The bundleflower that was grown with gamagrass was fine. Polycultures also seem to reduce or delay the onset of maize dwarf mosaic virus, which can be a problem on eastern gamagrass.” Farmers are especially intrigued by these results, since they seem to indicate that pesticides could be scaled back or even eliminated in polycultures. With the thought of pesticides gone, Piper and his colleagues began fantasizing about eliminating another petroleum-based crutch: nitrogen fertilizer.
Can the polyculture sponsor its own nitrogen fertility?
The question of how much nitrogen fertilizer a domestic prairie would need has not been definitively answered as of this writing. So far, though, signs are pointing to little or none. In experiments conducted with annuals, soil fertility always looks stronger in a polyculture, especially when legumes are in the plot. Tiny balls on the roots of a legume (such as Illinois bundleflower) are home to bacteria that have the ability to turn atmospheric nitrogen into plant food. As a result, legumes find a niche in nitrogen-poor soils, thriving where other plants falter. Plants growing near the self-sufficient legumes may also benefit from stored nitrates that return to the soil when the legume sheds a leaf, turns over a portion of its roots, or lays down its last.
In initial investigations of polycultures that include Illinois bundleflower, Piper found that, as predicted, bundleflower can grow beautifully and yield well even in poor soil, leaving the soil character actually improved. As Piper relates in scientific papers, “The soil nitrate concentration in four-year-old Illinois bundleflower stands at the poorer soil site was nearly identical to that on the better soil site despite very different initial nitrogen conditions.” Growing legumes is like having a crop that yields a harvest and simultaneously fertilizes your field. Which is why, of course, no prairie would be without them.
Despite the promise of The Land Institute’s work, we’re a long day away from finding gamagrass bread in our local supermarkets—twenty-five to fifty years, if these researchers are the only ones working. “We’re at the Kitty Hawk stage,” says Jackson. “We’ve demonstrated the principles of drag and lift, but we’re not yet ready to fly people across the Atlantic in a Boeing seven-forty-seven.”
They are ready to make some thrilling claims, however. In Eugene, Oregon, I saw Wes Jackson give an audience goosebumps with this statement: “After seventeen years of scientific research in pursuit of answers to four basic biological questions, The Land Institute is ready to formally state that our country can build an agriculture based on a fundamentally different paradigm than the one humans have featured for the last eight to ten thousand years.” Never losing his sly farm-boy humor, Jackson waited for the applause to break and then added, “And not only that, but we think it just might solve all manner of marital problems and end sin and death as we know it.” Although the room roared, there was no mistaking the seriousness of what Jackson and his friends had accomplished.
If the eroding Breadbasket is to be transformed by the work at The Land Institute, it will have sweeping repercussions. But our Breadbasket is only one small part of the world’s agricultural land. What Piper and Jackson and the rest would never dream of doing is
importing prairie agriculture everywhere. The natural systems farm, designed in nature’s image, would not look the same in all corners of the world, because ecosystems differ so drastically across the globe. “Take the difference between tropical rain forests and prairies,” says Jackson. “In the moist jungle, where water can be too abundant, you want water purgers—plants that can give off water vapor quickly. In the droughty plains, you want water hoarders.”
In short, the genius loci—“genius of the place”—should dictate the best agricultural system, given the local plant community, climate, soil type, and culture.
What can be imported from The Land Institute, Jackson says, is its methodology—its approach to learning a native system, intuiting its “rules,” and then slowly trying to raise a stable community of crops that mimics the structure and performs the functions of the wild one. As the following stories will show, the investigation is already under way.
RIPENING PROOF AROUND THE WORLD
“Do Nothing” Farming in Japan
Fifty years ago, when Wes Jackson was a boy weeding his family’s farm, a young man in Japan named Masanobu Fukuoka took a walk that would change his life. As he strolled along a rural road, he spotted a rice plant in a ditch, a volunteer growing not from a clean slate of soil but from a tangle of fallen rice stalks. Fukuoka was impressed by the plant’s vigor and by the fact that it was up earlier than those in all the surrounding cultivated fields. He took it to be the whisper of a secret revealed to him.
Over the years, Fukuoka would turn this secret into a system he calls “do nothing” farming because it requires almost no labor on his part, and yet his yields are among the highest in Japan. His recipe, fine-tuned through trial and error, mimics nature’s trick of succession and soil covering. In early October, Fukuoka hand-sows clover seeds into his standing rice crop. Shortly after that, he sows seeds of rye and barley into the rice. (He coats the seeds with clay so they won’t be eaten by birds.) When the rice is ready for harvest, he cuts it, threshes it, and then throws the straw back over the field. By this time, clover is already well established, helping to smother weeds and fix nitrogen in the soil. Through the tangle of clover and straw, rye and barley burst up and begin their climb toward the sun. Just before he harvests the rye and barley, he starts the cycle again, tossing in rice seeds to start their protected ascent. On and on the cycle goes, self-fertilizing and self-cultivating. In this way rice and winter grains can be grown in the same field for many years without diminishing soil fertility.
The neighboring farmers are curious. Whereas they spend their days cultivating, weeding, and fertilizing, Fukuoka lets the straw and clover do the work. Instead of flooding his fields throughout the season, Fukuoka uses only a brief dousing of water to head off weed germination. After that he drains the fields and then worries about nothing, except an occasional mowing of the paths between fields. On a quarter acre, he will reap twenty-two bushels of rice and twenty-two bushels of winter grains. That’s enough to feed five to ten people, yet it takes only one or two people a few days of work to hand-sow and harvest the crop.
Natural farming has spread throughout Japan and is being used on about 1 million acres in China. People from around the world now visit Fukuoka’s farm to learn both farming techniques and philosophies. The allure of this system is that the same piece of ground can be used without being used up, and yields can be consistently good. Instead of pouring money and energy into the farm in the form of petroleum-based inputs, most of the investment is made up front—in the farm’s design.
“It took me thirty years to develop such simplicity,” says Fukuoka. Instead of working harder, he whittled away unnecessary agricultural practices one by one, asking what he could stop doing rather than what he could do. Forsaking reliance on human cleverness, he joined in alliance with nature’s wisdom. As he says in his book, One Straw Revolution, “This method completely contradicts modern agricultural techniques. It throws scientific and traditional farming know-how right out the window. With this kind of farming, which uses no machines, no prepared fertilizer, and no chemicals, it is possible to attain a harvest equal to or greater than that of the average Japanese farm. The proof is ripening right before your eyes.”
Permaculture Down Under
When ecosystems are efficient and stable, they don’t require as much work as those kept in the vulnerable first stage of succession. Australian ecologist Bill Mollison, like Wes Jackson, advocates keeping some crops on the land for many years, to bring farming as close as it can come to nature’s efficiency.
For years, Mollison has worked on perfecting a system whereby small-scale farmers would set up a low-maintenance garden, a woodland, and an animal and fish farm and then become self-sufficient—fed, clothed, and powered by local resources that are literally right at hand. Designing with nature’s wisdom is at the core of this farming philosophy, which is called permaculture, for permanent agriculture. In permaculture, you ask not what you can wring from the land, but what the land has to offer. You roll with the weaknesses and the strengths of your acreage, and in this spirit of cooperation, says Mollison, the land yields generously without depletion and without inordinate amounts of body work from you. The most laborious part of permaculture is designing the system to be self-supporting.
The idea is to lay out crops so that those you visit most frequently are close by your dwelling (Mollison calls it edible landscaping) and those that require less vigilance are set out in concentric circles farther from the house. Everywhere, there are plants in two-or three-canopy schemes, that is, shrubs shaded by small trees, which are shaded by larger trees. Animals graze beneath all three canopies. Dips and furrows in the land are used to cache rainwater and to irrigate automatically. Wherever possible, permaculturists invite external forces such as wind or flooding to actually help do the work. They build windmills, for instance, or plant crops on floodplains, where they can enjoy a yearly pulse of alluvial sediment.
Choosing synergistic planting arrangements—using “companion plants” to complement and bring out the best in one another—is key to a successful agriscape. To maximize these beneficial unions, the permaculturist creates a lot of edge—transition zones between two habitats that are notoriously full of life and interaction. Mollison is also fond of using interactions between animals in place of high-energy inputs or machinery. One example is a greenhouse/chicken coop where plants are stacked on stair-stepped benches. The chickens roost on the benches at night, enjoying the warmth left over from the day’s solar radiation. They add to the heat with their own bodies, helping the plants survive the frosty dawns. In the morning, when the greenhouse becomes too hot, the chickens move into the forest for grazing. As they search for nuts and acorns shed by the planted trees, they comb the ground like rakes, aerating and manuring the soil while snatching up tree pests. Humans eat the eggs and eventually the flesh of these chickens, but in the meantime, they enjoy their services as cultivators, pest controllers, greenhouse heaters, and self-fed fertilizers.
Mollison learned this ballet of efficiency firsthand when he worked in the forests of Australia in the late sixties. As a researcher, he was trained to describe the biological world and leave it at that. But Mollison took the next step that is crucial in biomimicry: He saw lessons for streamlined living emerging from the forest and vowed to apply them to a new kind of agriculture. Today in Australia many farms are now working according to the permaculture principles he has popularized, and an international permaculture institute, with branches throughout the world, is training people to disseminate the technique. By mirroring nature’s most stable and productive communities, and then living right in the middle of them, Mollison believes, human communities can begin to participate in their beauty, harmony, and Earth-sheltering productivity.
New Alchemy Farm on Cape Cod
Another example of ecoculture sprouting in place of agriculture can be found on Cape Cod, at the offices of two of the country’s most innovative bioneers, John and Nancy To
dd. They formed the New Alchemy Institute in 1969 to design living spaces and food producing systems that would use nature as a model. The forest-in-succession was the conceptual guide for their totally self-sustained farm.
“Conceptually our farm begins at the bottom of the numerous fish ponds, and extends upward through the water to the ground cover formed by the vegetable and forage crop zone where livestock graze. It then rises through the shrub layer to the canopy formed by the trees that produce fruit, nuts, timber, and fodder crops. Following this plan we are hoping to maintain the farm in a dynamic state of ongoing productivity while it continues to evolve ecologically in the direction of a forest,” Todd writes in his 1994 book, From Ecocities to Living Machines. Like Mollison’s permaculture, New Alchemy’s farm is designed so that every living component has a multiple function—shading and fertilizing, for instance, as well as yielding an edible harvest. Wherever possible, the work of machines (and, by extension, humans) is replaced by the work of biological organisms or systems.
One of the Todds’ inspirations was Javan farms in Indonesia, where unconventional (to us, anyway) agriculture has thrived for centuries. The Javanese farm is nature in miniature, and it shows the restorative processes of planned succession. “Successional or ecological agriculture differs from ordinary farming in that it adapts to changes over time. In early phases, annual crops and fish ponds might dominate the landscape, but as the landscape grows and matures, a third dimension develops as tree crops and livestock come into their own. The key is to mirror the natural tendency of succession which, over time, creates ecosystems that are effective and stable utilizers of space, energy, and biotic elements.”