Dr. Stephen Carmody’s Native Cultigen Project aims to recultivate local edible weeds


By Thomas Davis and Lam Ho

Staff Writers

Photos courtesy of Dr. Stephen Carmody

Imagine if in as little as two decades the average American dinner looked drastically different. What if corn on the cob was considered a special Thanksgiving treat? After taking a critical look at the current viability of the American agricultural system, this future begins to seem possible. Soon staple crops such as grain, corn, and wheat could be endangered as the quality of American soil diminishes. Many of those taking action to keep American citizens fed are looking at how they can extend the utilization of soil, but they are simply delaying the issue. Visionaries like Dr. Stephen Carmody hope not to change how we grow on soil, but rather, what we put it in.

Carmody met Co-Chair and Associate Professor of Archaeology, University Archaeologist, and Boeckman Director of the Sewanee Environmental Institute Dr. Sarah Sherwood in 2010 when she reached out to a graduate student at University of Tennessee seeking a teaching assistant. Her contact there referred Sherwood to Stephen Carmody, who was working on his doctorate. With the Sewanee field school, they dug portions of two rock shelters (preserving the majority of these structures for the future) that provided data that eventually formed what became the Native Cultigens Project. What started as curiosity about the appearance and taste of plants from over 8,000 years ago became a passion to Carmody. For years, he studied the origins of agriculture, inspired by a class he took as an undergraduate student. Now, Carmody had done work in prehistoric caves and botany for his master’s thesis, and that cave site happened to be the primary site for Sherwood’s dissertation. From there, the two formed a symbiotic working relationship that helped to enhance their research and contribute insight to one another’s work.

Sherwood says, “We just hit it off in terms of how we think about stuff in the field. We have very complementary fields in terms of paleoethnobotany and geoarchaeology and what those bring to the larger research questions. And it takes a certain type of person if you’re spending long, hot days out there — you’ve got to entertain yourself. Stephen’s hilarious, so we have a lot of fun.” Today, he serves as a postdoctoral fellow in archaeology and as a visiting assistant professor. Identifying plants at these rock shelters over the years has led Carmody to some of the questions that drive his work today. “We originally decided we’d like to try to grow these plants mainly as a research idea. We thought, ‘We’ll watch them grow, see what they look like, have pictures.’ I can identify the seeds in a microscope, but I can step over these plants in my garden and never know what they are. And that’s true with most people; most people have never heard of these plants, for one, and being able to identify them is a whole other thing, to notice them on the landscape.” They are, after all, weeds.

“What’s cool is that it’s taking a logical, obvious idea — something that is right in front of us and pulling this prehistoric past out and saying, ‘Look at how these people used these plants that we’re just ignoring. In fact, we’re just pulling these plants as fast we can out of our gardens.’”

These overlooked weeds, so far in the past that growing them was the only way to know what they looked like in maturity, could be a local staple at McClurg in the next couple of years. Hoagland says that one short-term goal of the project would be serving maygrass or Chenopodium. Yet even more significantly is the idea that these weeds could be the answer to what some people consider to be an impending food crisis.

Carmody’s academic interest began to change form as his research progressed. Having developed a keen knowledge of the potential for an impending food crisis, Carmody saw a future for his native cultigens. “In the next 50 years, we are looking at having 3 billion more people, so where does the land come from? These crops, these plants that we’re looking to plant, because they’re weeds and local to the area, they don’t require fertilizer. They’re drought-tolerant, so they don’t require irrigation agriculture, we don’t think. They don’t have to be grown in a mono-crop, single row system, and they can be grown in areas like the uplands here, which most people consider marginal.” In these plants, Carmody sees an agricultural system that does not rely on old sciences, but instead diverges into a new branch of farming knowledge that relies on natural evolutionary achievements rather than engineered. And that, Carmody hopes, will prove to take less resources to grow, both in the form of labor and from the soil.

These archaic plants will have to prove they produce a large output before they can become viable on a large scale. “Each one of these plants is supposed to be able to produce 50,000 seeds. That’s a lot of food. So what does an acre of that look like? How much food could that produce? What’s the nutritional profile? We don’t know because no one’s tried to grow this as food since corn replaced these plants about a thousand years ago. No one’s relied on them for food resources since then.” With these plants, Carmody embarks on a journey of the relative unknown. Archaeological findings in the area confirm these crops were once relied on for sustenance and 50,000 seeds per plant is an impressive number.

While the project certainly shows promising results in planting and survivability, Hoagland expresses some concerns about the later stages of farming. “So the challenge we will encounter going forward is that these plants are a different size and shape and pattern than existing plants that are harvested mechanically.” In addition to this issue, the indigenous people did not complete the domestication of these plants. The still-primal nature of the specimens means that that the seeds don’t ripen all at the same time, forcing farmers to harvest multiple times or scientists to complete the domestication.

Hoagland touches on the fact that, despite the challenges of growing them on an industrial level, they could become a staple for home gardeners. “Even if it’s not suitable for industrial agriculture, it may be a plant that’s very suitable for home gardens, that people enjoy growing for their own purposes. There are a lot of plants that people cultivate in their own gardens that are not suitable, cannot be grown industrially,” she says.

This research is only the beginning, however. At some point, the indigenous people stopped using the plants in favor of crops like corn. In his research, Carmody hopes to shed some light on the decline of the original crops and, through this knowledge, prove that the time is ripe for these old plants to become staples once again. While Carmody and his research team were often hesitant to ruminate on the distant future of these plants, their re-discovery stands as an important potential improvement to American and possibly world-wide agriculture. In truth, the particular native cultigens Carmody studies could serve as a substitute across the world. However, every region has its own native cultigens with their own specific evolutionary advantages. Speaking towards the time ahead, Chenopodium cannot serve as a complete answer, however, the idea of native cultigens itself might. If Carmody’s research pans out (readers should do well to remember it is very early in development), scientists in other areas can put effort towards studying and growing their own native cultigens. The final image looks like a world growing plants on the soil they evolved to prosper on, creating firstly a more sustainable agricultural system and secondly a more diverse dinner plate across the planet.