MC partners with Mountain Homes and The American Chestnut Foundation to restore American chestnut tree

MC partners with Mountain Homes and The American Chestnut Foundation to restore American chestnut tree

July 13, 2018

Maryville College has partnered with Mountain Homes in Walland, Tenn., and The American Chestnut Foundation (TACF) to plant and maintain a disease-resistant American chestnut seed orchard that could eventually serve to reestablish the American chestnut tree in the area– and perhaps throughout the Great Smoky Mountains National Park.

Approximately 700 seeds were planted in late April on the property of Mountain Homes, which borders the national park.           

Chestnut blight

Until succumbing to a lethal fungus infestation called the chestnut blight (Cryphonectria parasitica) during the first half of the 20th century, the American chestnut tree was found in over 200 million acres of eastern woodlands from Maine to Florida, according to the TACF website. It is estimated that 4 billion American chestnut trees, or a quarter of the hardwood tree population, grew within this range. The U.S. Department of Agriculture now considers the American chestnut tree “functionally extinct.”

“The American chestnut was once THE dominant canopy tree in the Appalachian forests and has been suggested as perhaps even being regarded as a keystone species, or an organism that shapes the very environment in which it lives,” said Dr. David Unger, associate professor of biology at Maryville College and co-principal investigator on the Walland project with Dr. Drew Crain, professor of biology at Maryville College.

Unger explained that the American chestnut trees were of particular importance to wildlife because the trees bloom in June, thus avoiding blossoms being caught by a late frost, which results in a “mast (food) failure,” or no nuts being produced. Other hard mast producing species, such as oaks (which produce acorns), bloom in March and can be susceptible to the late frosts that occur in the Appalachian region, he said, adding that animals must seek alternative food supplies when a mast failure occurs.

“As an example, in years of severe mast failures in the Smokies, nuisance reports on black bears generally increase as the bears move into human-occupied areas seeking food,” Unger said. “As such, the American chestnut was the most consistent food provider for wildlife year after year when it was dominant. We may never know the overall impact on the carrying capacity (the amount of life an ecosystem can support) of our forests once the chestnut had succumbed to blight.” 

A perfect partnership

Crain and Unger helped establish a cooperative agreement between Maryville College and Mountain Homes in 2015 that would provide MC students and faculty members opportunities for teaching and research – and in turn provide Mountain Homes with scientific information about the plants, animals, ecology and other features of the property, which is located 20 minutes from the MC campus and is uniquely situated next to the Great Smoky Mountains National Park and various conservancies.

The American Chestnut Foundation was founded in 1983 “by a group of prominent plant scientists and lay persons who recognized the severe impact the demise of the American chestnut tree imposed upon the local economy of rural communities, and upon the ecology of forests within the tree’s native range,” according to the TACF website.

In 2017, Mountain Homes approached Maryville College about a partnership with the College and TACF to establish a seed orchard on their Walland property.

“Mountain Homes has a proven track record for conserving forest health; as an example, they have successfully managed to maintain their eastern hemlock trees in the face of the invasive insect that has devastated eastern forests, the hemlock wooly adelgid,” Crain said. “We at Maryville College are honored and thrilled to partner with them on this project to reestablish the American chestnut tree on their property.”

Through the partnership, Mountain Homes is providing land for the orchard and some funding, TACF is providing the initial seeds and technical expertise, and Maryville College will care for the trees and conduct research.

“The only way this project happened is through collaboration (between Maryville College, Mountain Homes and TACF),” Unger said. “That is how most all conservation efforts need to be to have any chance at success. The people of Mountain Homes are incredibly generous to give of their time, land and financial resources to make this project possible, and we are very appreciative of the relationship they have forged with Maryville College. The project itself represents an amazing opportunity for students to see ‘hands on’ what it means to try and restore ecosystems that have been impacted by human activity. The long-term positive effects of the restoration of the American chestnut are hard to fathom.”

Orchard planting

On April 28, a group of Maryville College biology students, Maryville College faculty members, TACF representatives and Mountain Homes residents gathered at Mountain Homes to plant 700 seeds on a one-acre site. When the trees are about two inches in diameter, researchers will inoculate the trees with blight and remove those that don’t continue to thrive.

“The overall goal of this project is to produce blight-resistant trees that will serve as nut producers to repopulate this area of the Appalachian forest with trees that are as close to the original genetically pure American chestnut, but with the ability to resist the blight that killed them,” Unger said.

Crain said the decades-long project will allow students for the next 20-30 years to visit the seed orchard to learn about and continue research on the American chestnut, adding that only a quarter of the orchard’s footprint was planted this year, leaving room for future plantings of other tree lineages provided by TACF. During the College’s bicentennial celebration in 2019, there are plans to plant two or three American chestnut saplings in one of the Maryville College fruit orchards on campus to be used for teaching purposes – and to educate the campus community about the American chestnut story. 

Undergraduate research

Kathryn Maley ’19, a senior biology major from Knoxville, Tenn., is researching the American chestnut tree for her Senior Study and spearheaded the April 28 orchard planting event as part of her project.

She decided on the topic after Unger, her Senior Study advisor, told her about the partnership between Mountain Homes, TACF and Maryville College – and the opportunity to oversee the planting of 700 American chestnut trees at Mountain Homes.

“Dr. Unger, knowing my passion for learning about plants and nurturing trees of my own, immediately offered the project opportunity to me, and I accepted without hesitation,” Maley said.  “This project is far bigger than me, my mentors or my Senior Study. It is about the restoration of a foundation species which once comprised at least 25 percent of our native hardwood forests in eastern North America and provided a reliable annual mast production which fed wildlife as well as humans. It is THE MOST important thing I have ever been a part of.”

Her Senior Study focuses on distinguishing differences in germination rate and growth rate of American chestnut hybrid seedlings from several different hybrid lines and families, Maley said.

“TACF has been working for years to breed a hybrid tree which maintains the physical morphology and fulfills the ecological niche of the American chestnut parent, while inheriting the blight-resistance of the Chinese chestnut parent,” Maley said. “This is clearly neither an easy nor a simple task, and there is still so much to learn about how these hybrids grow and how successful they are at defending themselves against the blight fungus.”

“Because TACF has kept great records of both the Chinese chestnut, which serves as the source of resistance, and the American chestnut parents, which comprise different families, I have the opportunity to study how successful each family tends to be in the native habitat of the American chestnut prior to their acquisition of the chestnut blight fungus,” she continued. “The hope is to find out whether some parents produce more competitive seedlings than others, which would be useful information to TACF as they continue their quest to breed the strongest, most resistant and genetically diverse hybrids possible that are able to defend themselves against the chestnut blight and repopulate the forests of eastern North America. Additionally, I am tracking exactly how much water the seedlings receive (both by hand-watering and by weekly rainfall) to determine how well the seedlings respond to natural variation in water availability, as very little information has been collected on what is required to help these hybrids succeed.”

While Maley will be working on the project for approximately a year, visiting the orchard weekly to water them and monitor the progress, she said she plans to be involved with the trees for even longer.

“They truly are like my children, and I will always be willing to return to give them whatever care is needed,” she said.

Unger said he hopes to identify a Maryville College student each year to oversee the project for a 12-month period, continuing the foundational work performed by Maley.

After graduating in May 2019, Maley said she plans to attend graduate school and eventually pursue a career in botany or forestry. She has an interest in forest ecology and preservation, and she hopes to do more field research on forests of eastern North America.

“This project will absolutely give me experience with study design, field research logistics, silvicultural techniques, and communication and collaboration between multiple organizations,” she said. “I have already met so many people from my aspired career field whose relationships could teach me valuable lessons and open doors of opportunity for my future. Not to mention, I am officially a mother to hundreds of trees which will outlive me and hopefully contribute to the reforestation of this amazing species! They are my personal mark on history.”


Maryville College is ideally situated in Maryville, Tenn., between the Great Smoky Mountains National Park and Knoxville, the state's third largest city. Founded in 1819, it is the 12th oldest institution of higher learning in the South and maintains an affiliation with the Presbyterian Church (USA). Known for offering its students a rigorous and highly personal experience that includes an undergraduate research requirement, Maryville College is a nationally ranked institution of higher learning that successfully joins the liberal arts and professional preparation. Total enrollment for the Fall 2018 semester is 1,146.