Environmental Almanac: 'Resilient' agriculture in works at South Farms
When people think about alternatives to the intensive industrial agriculture that dominates the Midwest, they generally think first about things like organic fertilizers and integrated pest management, a return to practices that have worked in the past.
Others are envisioning — and implementing — alternative forms of agriculture based on completely different principles, among them two energetic young people who are currently University of Illinois graduate students.
They are Kevin Wolz, who is working on a Ph.D. in the Program in Ecology, Evolution and Conservation Biology under the direction of Evan DeLucia, and Ron Revord, who is completing a Master's thesis that uses genetic analysis to forward the development of disease-resistant hazelnut cultivars. They are trying out this new form of agriculture on a 5-acre plot at the UI South Farms called the Woody Perennial Polyculture (WPP) site.
The WPP employs principles of what is known more generally as permaculture, which favors systems to serve human needs that are based on natural systems rather than constant technological intervention. In agriculture, this means replacing the annual crops that now account for nearly all of what we eat in one way or another — corn, soybeans, wheat and rice — with perennial ones and replacing the practice of growing only one crop on a site with cultivating a diverse, complementary suite of crops, a suite dominated by shrubs and trees.
The WPP was established in the spring of 2012 with support from UI professors Michelle Wander and Bruce Branham. It features four half-acre blocks of polyculture alternating with four blocks of the same size devoted to corn and soybeans, which are cultivated just as they would be on a typical Champaign County farm.
Within each polyculture block are six rows of two types. One type features apple trees spaced 24 feet apart as the tallest component. Between the apple trees grow two shorter layers, a hybrid variety of hazelnut that's maintained as a multistemmed shrub and raspberries.
The other type of polyculture row features an overstory tree, a hybrid chestnut that will reach a height of 30 feet when mature. The chestnut trees will not produce a crop for some years, but growing between them are red and black currants. These will tolerate the shade of the chestnuts as they grow and they already produce a substantial crop.
A perennial pasture mix of grasses and clover, which is cut for hay, separates the various blocks. The preference would be to keep animals on the farm to graze between rows, but rules prohibit the integration of livestock and crops on campus property.
On a recent visit to the WPP site, I asked whether such a system could ever produce the way cornfields do in Illinois. In reply, Revord pointed out to me that's really not the right question to ask.
He said that in terms of money, it makes more sense to compare the potential net income of the two types of agriculture. The conventional fields can produce high yields year after year, but those yields depend on high inputs year after year as well — annual tilling and planting, applications of fertilizer, herbicide and pesticides, etc.
The case is different with woody perennial polyculture. There, costs are high in early years while plants are being established and nurtured, and revenue is low, since some parts of the system are not yet producing. As the system matures, however, costs decrease substantially, since there's no need for yearly planting and limited pest management to do. At the same time, yield rises, as does revenue.
Wolz emphasized that the aims of restoration agriculture (his preferred phrase) go beyond money, too. "Our goal is a system that simultaneously produces food for people and restores ecological integrity to the land."
In order to gauge how well the polyculture blocks function compared to the conventional fields from an ecological perspective, WPP researchers are studying a large set of interrelated topics.
Among them are carbon sequestration, nitrogen leakage, water use efficiency and support for biodiversity.
When I was there, the polyculture blocks were alive with bees and other pollinators, as well as birds. In contrast, the corn plots seemed devoid of any life other than corn plants.
Revord noted that such a lack of diversity is widely recognized as a potential weakness in other aspects of our culture. He pointed out, "We learn early on not to put all our eggs in one basket, and yet that's exactly what most of our current agriculture does. What we're working to develop is an alternative that's more resilient."
Rob Kanter is a lecturer with the UI School of Earth, Society and Environment. Environmental Almanac is supported in part by the UI Institute for Sustainability, Energy and Environment and can be heard on WILL-AM 580 at 4:45 and 6:45 p.m. on Thursdays.