Photo courtesy of Pattie Quackenbush
By Mitch Ryals
COLUMBIA, Mo. — Soil is alive. It moves and changes below our feet without a second thought or a thank you from above. Yet soil health and composition has a huge impact on our lives. It affects the food that grows in the ground. It affects forests, which are used for timber and fuel and are home to thousands of plant and animal species. It can even help cure infections. In the late 1940s, soil from Sanborn Field, east of the MU campus, contained an actinobacteria called Streptomyces aureofaciens that helped develop the antibiotic aureomycin.
“Most people, when they walk outside they don’t think about what’s in the soil,” says Pattie Quackenbush, a doctoral student studying earthworm ecology. “Soil is not this static material that you walk on, you get under your fingernails or you track in the house, and it makes your mom upset… It’s this dynamic, living, breathing, ever changing material. And I don’t think enough people think of it that way.” But Quackenbush does. She’s been studying soils and earthworms since 2009 and doesn’t intend to stop soon.
Quackenbush is a bit of an enigma, and she’s still trying to figure herself out. She’s a doctoral student studying earthworms and soil in the College of Agriculture Food and Natural Resources at the University of Missouri-Columbia. She has dark hair with a streak of bleach blonde running through her bangs. Pink or purple swirls hang from her gauged ears depending on her mood, and she’s often clad in khaki cargo pants and a plaid shirt, again colors varying with her disposition. Quackenbush is also a Native American, a descendant of the Mohawk Nation in northeast United States and parts of Canada. Her skin is lighter than the stereotype, so she is frequently asked how much Native American blood she has.
“I’m not really white, I’m more of a pink,” she says. “But that’s a struggle. It’s like what does this all really mean? Is it a burden? Is it something I need to incorporate into my identity?”
Growing up in Indiana, she was discouraged from embracing her Native American ancestry. It wasn’t until college when she found the Native American Educational Cultural Center at Purdue University that she felt comfortable exploring what it means to be Native American. She’s talked with members of other tribes to try to understand the culture a little better, and she hopes to learn the language she vaguely remembers her grandmother speaking to her as a child.
When Quackenbush is asked questions such as “what are you?” or “how red are you,” she pauses for a moment. Should she use the question as a teachable moment? Or should she wallow in its ignorance? Rarely if ever does she opt for the latter. Instead of asking “how red are you” or “what are you” the question should be simply, “what’s your heritage,” Quackenbush explains.
Although she identifies as a Native American because of the Mohawk blood from her dad’s side of the family, she is not allowed to enroll in the Mohawk Nation. The tribe requires a member’s ancestry be traced through maternal lines. So why does she identify with a tribe that doesn’t recognize her as one of its own? Her grandmother, Mary Quackenbush, is to thank for that.
From the time Quackenbush was about 3 years old, she helped her grandmother in the garden flanking her house, which sat on about five acres of land in Yoder, Ind. They grew just about everything, Quackenbush says. Blueberry and raspberry bushes, strawberries, green peppers, banana peppers and Serrano peppers. She remembers multiple varieties of tomatoes — roma, grape, beefsteak — and a traditional Native American garden called a Three Sisters garden, which consists of sweet corn, beans and squash. The Three Sisters garden was a lesson for Quackenbush in the natural relationships between plants, which also provided inspiration for her graduate research.
First you plant the corn, Quackenbush says. Wait for the stalks to get about four feet tall, and then plant the beans and squash. The four-foot corn stalks provide a natural pole for the bean vines to climb, and the bean vines provide more stability to the corn stalks. The beans also improve the soil’s overall fertility by adding nitrogen. The squash is shallow-rooted and act as mulch for the garden. Its vines also shade out unwanted weeds.
“She almost had a preternatural sense about how to take care of plants,” Quackenbush says of her grandmother who was full of horticulture tips. For example, when geum first appears in the spring, it is time to plant strawberries. They’re from the same family, Rosaceae. Violet is safe to eat if you’re lost in the woods. It’s full of vitamin C. And stinging nettle, a plant that irritates the skin like poison ivy, commonly grows next to jewelweed, which is a plant that can relieve the irritation.
Quackenbush credits her Native American heritage and her grandmother’s guidance as the source of her passion for soil and earthworms, a passion that’s led her through undergraduate and master’s coursework and landed her in mid-Missouri for doctoral research.
It was while taking an introduction to ecology course at DePauw University that her grandmother’s lessons and her affinity for the outdoors meshed. She felt at peace in nature; she felt like she belonged. Seven years and a transfer to Purdue University later, Quackenbush graduated with a degree in botany, but she wasn’t done. After a semester-long break, she began master’s classes and concentrated her research on earthworms.
“It wasn’t until I started the literature review for my master’s work that I realized we know a lot about (earthworms), but we still have a very limited ecological understanding to an extent,” she says. “We understand their locomotion and stuff that they eat, but what are their real impacts on the systems around them?”
By the time she finished her master’s degree she published two research articles. The first looked at the relationship between invasive earthworms (also known as common nightcrawlers) and garlic mustard plants, an invasive species in the United States. Invasive species are those that are not native to the area and compete with native species for space and nutrients. Common nightcrawlers and garlic mustard plants are frequently found in the same areas and negatively impact surrounding native species, according to the study, but relatively little is known about how the two invasive species interact. The study found that common nightcrawlers prefer to eat garlic mustard seeds to most of the other seeds used in the experiment. Results from the study indicate that common nightcrawlers could reduce the amount of garlic mustard seeds in the soil and therefore the plant’s ability to return the following year, though more research over a longer period of time is needed to know for sure.
The second article that resulted from her master’s research looked at earthworm densities in forests that have been untouched for 80 years or more, called old-growth, compared to forests whose vegetation was allowed to grow back after a harvesting event, called second-growth. The results of the study indicated that nonnative, invasive plants and earthworms pervasive in Indiana hardwood forests and could reduce the number of native plant species.
Earthworms in Missouri:
Quackenbush’s doctoral research, which she plans to start this spring, also involves earthworms. First she’ll determine how many and what kind of earthworms are in the soil at three locations in mid-Missouri. Each of the locations represents a different level of land use ranging from continuously managed and researched to largely unmanaged.
“So we’re hoping that we can identify some trends or some sort of predictors or factors that help us to explain what we’re seeing up top by what happens below ground,” she says. Quackenbush will be looking to identify earthworm species as well as classify them into three ecological categories: epigeic, endogeic and anecic.
Epigeic earthworms are small and live near the soil surface and munch on leaves.
“They’re primarily involved in processing the crude organic matter prior to further breakdown by microorganisms,” says Dr. Robert Kremer, an adjunct professor of soil sciences at MU and a USDA microbiologist. Think of epigeic earthworms as the chewing and saliva phase of food digestion in humans. They “set the stage for good decomposition and formation of soil organic carbon matter,” Kremer adds. The presence of organic carbon in the soil is one indicator of soil health.
Endogeic earthworms, the second category, are slightly bigger and live slightly deeper in the soil. They move horizontally and continue the breakdown process. They mostly munch on fine root tips, fungi and microorganisms such as protozoa, paramecium and bacteria.
Anecic earthworms, the third category, move vertically and move materials from deep within the soil to near the top and vice versa. Endogeic and anecic earthworms both eat vegetation and plant seeds and mix it with other soil material in their guts. This mixing makes the material more fertile before it’s released back into the soil. However, their movement in the soil is just as important. Simultaneous vertical and horizontal movement of these two groups of worms creates a mini-till effect, mixing and combining the soil material, which is important for good soil composition, Kremer says.
The second part of Quackenbush’s research hypothesizes a relationship between exotic earthworms and sericea lespedeza, an invasive plant species found in throughout Missouri. It will also examine the relationship’s possible influence on soil health.
“Some invasive earthworms eat the beneficial fungi that many native plants need to associate with in order to grow properly,” Quackenbush says. “So they create theses zones of basically no fungi, and those plants that require this particular fungi can’t grow.” Invasive plants, like sericea lespedeza then take over.
Sericea lespedeza, native to Asia, was brought to the U.S. in the late 1800s, according to the Missouri Department of Conservation. The plant was used to improve land and soil conditions, prevent erosion, provide livestock with forage and provide wildlife cover.
However, since its introduction to the U.S., sericea lespedeza has been found to be negatively allelopathic, which means it releases chemicals that inhibit growth of other plants, decreasing biodiversity, according to John Knudsen, a private lands regional supervisor for the Missouri Department of Conservation.
“It encroaches on native species in many different settings,” Knudsen says. “It also has unbelievable seed production, producing millions of seeds per year, and it’s unpalatable to cattle.”
By researching the relationship between earthworms, and sericea lespedeza, Quackenbush hopes to add to the growing body of research on earthworms and invasive plants.
“I’m not expecting Nobel Prize winning results, but if we could show that there is enough of an effect that alters what we see in future use, then maybe we can get more research to look at why this occurs and what we could do to stop it or prevent it,” she says.
There are many indicators of soil health. Earthworms’ presence is generally considered to be an indicator of good soil health, says Dr. Randy Miles, an associate professor of soil sciences at MU and the director of Sanborn Field. But in addition to the number and types of earthworms in the soil, Quackenbush will measure organic carbon and phospholipid fatty acids as soil health indicators.
“Soil organic carbon is one of the most important constituents of the soil due to its capacity to affect plant growth as both a source of energy and a trigger for nutrient availability through mineralization,” according the USDA’s website.
As microorganisms break down material in the soil, they produce carbon. By measuring the amount of organic carbon in the soil, Quackenbush will be able to determine the activity level of microorganisms. The more active the microorganisms, the healthier the soil.
If active carbon is an indicator of what is happening in the soil, phospholipid fatty acids are an indicator of which organisms are doing the work. The cell membrane of each organism in the soil is made up of distinct phospholipid fatty acids. Quackenbush will be able to determine which organisms are present in the soil by identifying specific phospholipid fatty acids.
“Some of those organisms are pathogenic, some of them are beneficial, some are a little of both,” Quackenbush says. “But it definitely helps us paint a picture environmentally within this sample in this location.”
Quackenbush sits slouched on a couch in the Multicultural Center before a Four Directions: Indigenous Peoples and Allies meeting. Accompanied by two other members of the student organization, she’s wearing a bright plaid button down shirt and cargo khaki pants. Purple swirls hang from her gauged ears and her tongue ring shines briefly as she yawns. Four Directions has about 10 active members, mostly female and all graduate students save one junior undergraduate. The group was originally formed in the mid-1990s but disbanded in 2003 after all the members graduated. Quackenbush and Anastacia Schulhoff, the vice president and president respectively, helped revive the group in 2012.
Native Americans are less than 1 percent of the student body at MU, and the meeting turnout reflects that minority-among-minorities status. Only three members are present, though they’re grateful that the three nonmembers in attendance are showing interest in the organization. Elections are coming up in April, and Schulhoff and Quackenbush would like to be able to pass the reins onto others who can keep the group going after they leave.
They talk about ways the group can recruit new members. A table on the first floor of the Student Center during lunchtime, or maybe a table during summer welcome. They’re also planning a field trip to Haskell Indian Nations University in Lawrence, Kan., or maybe to a powwow in Tulsa, Okla., in the summer.
After the meeting, Quackenbush and Schulhoff are asked to talk to a group of Alternate Spring Breakers. They’re traveling to the Crow Creek Reservation in Fort Thompson, S.D. and want some advice on how to act and what to expect.
“Check your religion at the door,” Quackenbush says. “And don’t be surprised if they look down when speaking to you,” Schulhoff adds. Although avoiding eye contact might be interpreted as disrespectful in some cultures, it’s a sign of respect in Native American culture. “And don’t ask how ‘red’ they are,” Quackenbush says. “I wouldn’t ask you how white or how Asian you are.” Although she admits sessions like these can be emotionally draining, she enjoys teaching those unfamiliar with Native Americans about the culture. She feels that if she can educate even one person about Native American culture, she’s made an accomplishment.
Although her Native American heritage has caused her some internal conflict and she’s not allowed to officially enroll as a member of the Mohawk Nation, she’s grateful to her grandmother for introducing her to Native American culture.
“Indigenous identity is complex and always evolving,” she says. “And we’re always trying to figure out where we fit into greater society.” As her search for a place in society continues, ask her a question about Native American culture. She enjoys those teachable moments. Or ask her about earthworms. She knows a lot about those, too.