Wildflower is published quarterly by the Wildflower Center. Its content is national in scope with articles about the conservation and use of native plants as well as news from the Wildflower Center. A subscription is provided to Wildflower Center members as a benefit of membership.
Could native and well-adapted perennial crops be the answer to food shortage?
Article by Sandra D. Lynn
THE FIRST TIME I VISITED THE LAND INSTITUTE (TLI) in Salina, Kansas, I looked around at its surrounding prairie landscape and wrote, "This is tamed countryside calm, verdant, with rivers relaxed in the abundance of water."
I saw no dry riverbeds choked with stones, precipices or dust devils none of the harsh wildness of southern New Mexico's Chihuahuan Desert where I lived. I was visiting in order to learn more about TLI's innovative work with native perennial sunflowers. Kansas, the Sunflower State, looked to me like a place where fields of sunflowers could grow fat with seeds, where people could still make a living on the land, a place assured of a future.
But the very existence of TLI in Salina argues against that comforting sense of assurance. Its mission statement explains "...The Land Institute seeks to develop an agriculture that will save soil from being lost or poisoned while promoting a community life at once prosperous and enduring." Along with a network of plant scientists and agricultural ecologists around the world, TLI is engaged in revolutionizing the way we grow food.
A look at current farming
Let's look at the pattern that has dominated farming for thousands of years. With either a pointed stick or a $350,000 tractor, a farmer breaks up the soil to allow for planting the seed; the seed grows into a mature plant, often only with the addition of large quantities of water and chemicals; the crop is harvested; the broken land may lie fallow over long periods of time (even a year or more), during which soil may blow or wash away. Eventually the whole process must begin all over again and again and again. What if those crops grew to fruition year after year without the need to break up the soil? What if less water and fertilizer had to be applied because the plants' roots reached deeper and were able to enhance fertility through long-term partnerships with microorganisms? Do we know what that would be like?
Yes, because we grow some of our food in orchards. Year after year, given appropriate care and growing conditions, the trees produce nuts or fruits. In other words, if the crop plant is a perennial, it remains rooted and produces a crop for harvest each year without plowing and replanting, just as your garden grapevine does. If, in addition, it is a native perennial, it will grow with all the advantages of natives less need for irrigation, pesticides and fertilizers.
But the grains and oil seed crops that now provide the largest percentage of human nutrition at 70 percent are not perennials. They are primarily annual crops from the grass family, such as wheat, rice and corn. The annual oil seed crops are primarily from the sunflower, mustard and legume families. Other important food crop plants are annual legumes, such as beans. Replanting these annuals again and again requires huge inputs of human and fossil energy, water and chemicals. Also, these efforts expose the soil to erosion and degradation in fertility.
Turning agriculture around
Jerry Glover, Ph.D., is a science and technology fellow working as an agricultural ecologist with the U.S. Agency for International Development (USAID) while on leave from TLI. Named an Emerging Explorer for 2010 by National Geographic, Glover and TLI colleagues are indeed exploring the possibility of turning agriculture around from growing annual crops far removed from their origins to growing perennial native (and naturalized) plants.
He thinks that crops from perennial plants are the answer to a global food crisis that could be created by an increasing human population and diminishing quantity of fertile cropland. At TLI, Glover and colleagues are looking at perennials that have evolved successfully in their native American Midwestern prairie as potential food crops. Glover says, "It's time to put natural plant communities back in charge of the landscape.
"In the long term that will mean developing and growing perennial grain crops in such a way that they function more like the natural plant communities displaced by agriculture and, at the same time, produce abundant yields of grains."
Today's farmers don't have available to them the seeds of perennial grains they could grow as large-scale crops. TLI scientists and others around the world want to someday develop and distribute domesticated grain crops like perennial types of maize, sunflowers, rice, wheat, legumes and oilseed crops. Researchers at TLI have worked with bundleflower (Desmanthus illinoensis), the Eurasian native intermediate wheat grass (Thinopyrum intermedium) and Maximilian sunflower (Helianthus maximiliani).
What it takes to farm perennials
The process of converting wild plants into successful agricultural cultivars requires years. Annual crops we now take for granted were once, hundreds or thousands of years ago, developed from native plants that scarcely resemble their contemporary agricultural versions. Sunflower is a good example. Native Americans began the process of turning native annual sunflowers (Helianthus annuus) just like the ones that still brighten our roadsides in the summertime into an agricultural marvel.
Today we could still go out and harvest wild sunflowers for their seeds (I've done it), but they are so small and hard to turn into food we wouldn't want to have to depend on them for dinner. Instead, over millennia, Native Americans, Russians and others transformed the annual sunflower so that today millions of acres of large-headed, large-seeded sunflowers around the world provide high-quality cooking oil and protein for humans and other animals. So how will TLI develop perennial sunflowers and other natives into crops?
Plant biologist David Van Tassel, Ph.D., explained that at TLI they are using traditional breeding methods that involve three basic steps: selecting good candidate plants, collecting genetically diverse seeds to begin with and selectively breeding for preferred traits, such as large size of seeds.
Results are accumulating from plant breeding that has been underway for a little more than a decade. For instance, he points to research by TLI plant breeder Lee DeHann, Ph.D., who "has selected wheatgrass individuals with much greater seed production and larger seeds. He has more than 30 acres in production, using standard grain planting and harvesting equipment, and has been having the grain milled in a commercial mill, for further food quality and nutrition testing."
This new version of perennial wheatgrass now has a trademarked name, Kernza. Someday we may be eating Kernza for breakfast. As we do, we can contemplate all those "amber waves of grain" sinking deep roots into their American landscape.
Food for a changing climate
In an utterly different climate and landscape from the Kansas prairie, an authority on Sonoran Desert plants, Dr. Richard Felger, Ph.D., is gazing into his own crystal ball seeking our agricultural future. He has found native plants that he believes could feed a growing population on a planet with a changing climate that is warmer, drier in some places but much wetter in others.
Felger is presently associated researcher at the University of Arizona Herbarium and research associate with the Sky Island Alliance, both in Tucson. He has conducted research in deserts worldwide with the hope of addressing world hunger through agricultural independence for arid and semiarid regions. Like the researchers at TLI, his concepts include no-till farming and, as he puts it, "fitting the crop to the environment, not changing the environment to fit the crop."
He and his research associates Edward Glenn and Susanne Pearlstein have decided to focus their efforts on the Mexican grass nipa (Distichlis palmeri) from their base at the University of Arizona. Another associate, Neil Logan, is based in Hawaii and studies mesquite (Prosopis spp.) a nitrogen-fixing legume there and in South America.
Felger explains how he began to study nipa: "When I was a sapling, I had some handsome funding from the Rockefeller Foundation to travel worldwide in search of possibilities for new crops." He visited arid regions and investigated local plants, knowing that only 15 to 20 percent of the plants in any given area might be edible and only a few of those actually could become staples of the diet.
What Forms Will These New Crops Take?
ACCORDING TO DAVID VAN TASSEL, Ph.D., at The Land Institute, "Our final products will likely be breeding populations (germplasm) rather than released cultivars. Breeders in each region will need to take the breeding population and do additional selection for adaptation to local conditions." For more information about the ongoing work at The Land Institute, check www.land institute.org. Van Tassel says the results of perennial crop development may be:
– a domesticated plant of the same species as
the original native perennial, i.e., a plant that
has acquired some new traits but has not
become taxonomically different. Example: a
Maximilian sunflower (Helianthus maximiliani)
that produces one larger flower head
instead of numerous small ones.
– a new, artificial species that resulted from crossing two native species. Example: annual sunflower (Helianthus annuus) crossed with perennial Jerusalem artichoke (Helianthus tuberosus).
– a new perennial version (race) of an original annual grain. Example: perhaps a perennial rice developed in China.
Richard Felger points out that "field tests of different mesquites are underway in various regions of the world High-yielding, pest resistant, flavorful candidates exist in test plots and remnant forests." For more information on mesquite as a food crop, see www.desert harvesters.com. For more information about the species and their distribution, see the Wildflower Center's Plant Database.
As an ethnobotanist, botanist and ecologist specializing in desert plants, Felger was already acquainted with the indigenous use of mesquite species and nipa as foods in North and South America, and he finally decided that they offered the best possibilities for developing major new food crops. Both types of plants are adapted to and thrive in heat, drought and, in the case of nipa, salinity and also both provide good sources of plant protein.
Many people in the U.S. are familiar with the mesquite tree and aware of the use of mesquite as a cooking fuel to impart flavor to broiled meat and also as nectar for bees in the making of honey. (Felger points out that Kiawe white honey from Peruvian mesquite introduced into Hawaii is "considered one of the finest gourmet honeys in the world.") However, relatively few people know that mesquite has been used for basic human food. Some mesquite species produce a high yield of edible pods, which have pulp and seeds that when ground produce a delicious flour (see sidebar). Native peoples, including those in the southwestern United States and arid regions of Mexico, once prepared and consumed millions of pounds of mesquite pods annually.
Nipa is another story entirely. The common name of this grass comes from the native people of the Colorado River delta, and it is little known by anyone other than the Native Americans in that region. It can flourish in both seawater and fresh water, an enormous advantage in arid parts of the world where the salinity of water is a problem for agriculture.
The native Cocopa people from whom Felger learned about nipa did not cultivate the grain but rather gathered it when it washed ashore in windrows or harvested it from rafts. They parched the grain and then ground it into flour. Felger says, "As the rise in sea levels causes a reduction in delta land in Asia, nipa could be grown in standing water." Mesquite already has been widely used as a native, perennial wild food plant. Nipa has not, and the prolonged effort needed to transform it into a crop plant is only beginning.
But let's put emphasis on that word beginning. On a planet facing climate change and a growing population, production of food ranks high on the list of big worries about our future. But some scientists and organizations are not just worrying: they are actively betting on wild perennials to come to the rescue of soil, water and hungry humans. They are envisioning a world in which natural plant communities will be back in charge of their landscapes.
Sandra D. Lynn is an Albuquerque-based writer with a passion for plants.