Millions of dollars have been spent in researching new and better ways to feed the hoarding masses and yet the best solutions may be what nature provides in her mature ecosystems whether it be a grass-filled prairie, the lushness of a tropical rain forest or a sun washed desert. The idea is that the agriculture of an area would imitate these ecosystems that thrived before settlement.
In that light The Land Institute in Kansas has spent the last 25 years studying how a perennial (ever renewing itself) polyculture (more than one crop grown together) might be the answer to feeding our ever expanding population without creating more problems. Wes Jackson, the leading force and inspiration behind the Land Institute believes that a natural prairie system could be a veritable grain factory complete with built-in pest controls and fertilizers. Jackson, his staff and a handful of volunteers are on a quest to reconnect how we grow our food with the natural processes of life. They acknowledge that our agricultural system needs a total overhaul. We have replaced natural systems with ones that are totally alien and have waged war on nature itself.
In a wild system, plants live in community, build topsoil, fight their own pest battles, and manufacture fertilizer. It is the biodiversity in a natural ecosystem that accounts for an endless array of functions that provide stability and growth to that system. There are the plants that fix nitrogen, the deep-rooted ones that burrow for water, the shallow-rooted ones that soak up the gentle rains, the fast growing ones that provide weed smothering shade early in the spring, the ones that repel pests and the ones that supply food and homes for the good bugs. Even more remarkable is that 70 percent of the living weight of this system lies underground in natures own Internet and plumbing network. Roots and runners form a thick weave that captures moisture and nutrients from the depths. In every teaspoon of soil are thousands of species of bacteria and bugs that process fallen leaves and dead roots into a nutrient rich humus.
When we ripped out our natural systems, tilled the soil, and planted monoculture crops doused in chemicals, we destroyed much of our natural inheritance for healthy food production. Instead of taking our lessons from the perfect teacher, which was the very systems we replaced, we arrogantly thought we could do better. The results are severely depleted topsoil, super-bugs that have become resistant to our most potent and toxic brews, increased cancer rates, poisoned water tables, and flounder genes in tomatoes.
Jackson, a fourth generation farmer and somewhat of a maverick, bucks the traditional monoculture farming practices passed down through generations. As a youngster the hardiness of the natural prairie intrigued him. There was a rightness to it all. Studying for his Ph.D. in genetics at North Carolina State his advisor once declared that wilderness was the standard by which we must judge our agricultural practices. That statement set in motion a life long yearning to create a new system of agriculture that would use nature as its model. After a stint at the University of California at Sacramento creating their Environmental Studies program, Jackson moved his family to Kansas and created The Land Institute. Formed in 1976, it was originally a school for sustainable living practices. Today the Land Institute is on a mission to design a domestic agricultural system that functions like a prairie. To that end many years went into just observing a natural prairie at work and cataloguing the seemingly infinite variety of plants growing at any one time.
The first principle that struck the researchers is that ninety-nine point nine percent of the plants are perennials. Covering the ground throughout the year, they act as big sponges, holding the soil against wind and softening the force of raindrops. Perennials as it turns out are also self-fertilizing and self-weeding. Every year organic matter is added to the soil due to the death and decay of thirty percent of their roots. In the spring before weeds have a chance to emerge from their seeds, the remaining perennials burst forth with such abundance the weeds never have a chance.
The second principle that stuck out is the amazing diversity of plant life. There could be over two hundred different species on any given acre of land. There is not just one kind of warm season grass, but perhaps forty different kinds. There might be twenty different varieties of nitrogen-fixing legumes. Nature banks on this type of diversity in order for its systems to have enough ammunition to ward off pests, drought and other anomalies. Pests often prefer one particular host plant species. With a large variety of species in one field, pests have a harder time zeroing in on their food. Some plants survive a dry season while other die out. The species composition remains the same, but different species flourish at different times.
The third principle of a natural prairie is the ever-present four plant types: legumes, cool and warm season grasses, and composites such as golden rod and asters. Even though the species may vary, there is always a variety of all four. Each type provides an important function to serve the whole.
The job of the Land Institute was to find perennial grains that could be produced in a natural prairie system with high enough yields to be taken seriously as food sources. Given additional strict criteria such as hardiness, good taste and ease of threshing, they ordered nearly five thousand different types of seed from various resources and planted them in nearby fields. Those that lasted the winters and showed promise became part of their breeding program.
That research narrowed the candidates down to four hardy perennials that fit the bill. The first was eastern gamagrass (Tripscum dactyloides), a relative of corn. Gamagrass is a warm season grass that can be ground into cornmeal and baked into bread. Next came the Illinois bundleflower (Desmanthus illionoensis), a tall-growing legume that produces a rattle of seed-pods; and mammoth wildrye (Leymus racemosus), a cousin of wheat that is drought tolerant. The Maximilian sunflower (lianthus maximiliannii), completed the quartet and provides oil-rich seeds with a variety of uses. They also came up with two annuals they hybridized with perennials to round out the breeding program, milo grain sorgum and Johnsongrass.
They have since cross-pollinated each species to come up with the best of the best and increase the positive traits. The next step was to grow them in a polyculture.. They started to grow their prize seeds in various combinations, but soon realized the variations were endless. How does one quickly recreate a system that originally took thousands of years to develop? They found help in James Drake and Stuart Pimm of the University of Tennessee. Using both computer models and aquatic organisms, Drake and Pimm experimented with various combinations of species, letting them work out who will survive and in what ratio. With this information, the Land Institute created sixteen plots to try various mixes. What they are discovering is that for the first and second year the fields look awful with lots of annual weeds. However in subsequent years the perennial seeds really take off. Nature sorts out what works and what doesn’t and establishes a stable community of plants.
The Land Institute is now working out the management of such a system, when to mow, when to leave alone, if and when to burn, when to turn it over to grazing and how to harvest the various crops in the field. This system is more like sustainable forestry – waiting until the system is mature before harvesting – and then reaping only what is ready and leaving the rest to mature. A polyculture provides the best protection against disaster. There will always be varieties that will flourish in any given conditions.
The replicated prairie is proving that it can provide high enough yields to compete with a monoculture, that pests and disease can’t get a foothold due to the large variety of plants in one field, and that it can provide its own nitrogen with various legumes. Jackson believes we can fundamentally change our agricultural systems using this model of a perennial polyculture. It would look different in a forest, a desert or in a wetland, but the basic premise remains the same – use wilderness as our model.
Still a ways off from replacing our monoculture practices, the work of The Land Institute holds great promise in restoring our food production system to one that is humane, ecologically sound, and safe for all.
Suggested reading: Much of this article was derived from Janine M. Benyus’ brilliant book Biomimicry, published in 1997 by William Morrow and Co. For more
information on The Land Institute you may contact them at: 2440 W. Water Well Road, Salina, KS 67401, phone (785) 823-5376, fax (785) 823-8728, e-mail – theland@landinstitute.org, and web site: www.landinstitute.org.