Revitalizing the American Chestnut: The Chestnuts and Bolts with Eric Griffin
Lili Jones | February 21, 2024
Less than a century ago the American chestnut tree was one of the dominant tree species throughout the eastern United States, until multiple invasive pathogens killed them en masse. Today, Warren Wilson College (WWC) is working with The American Chestnut Foundation (TACF) and Clemson University to develop pathogen-resistant trees in an attempt to revitalize the American chestnut across the country.
In 2001 and 2018, there were two major chestnut plantings in WWC’s chestnut orchard on Christmas Tree Hill off of Fortune Trail. Two adult trees stand as a result of the 2001 plantings. They are scraggly and worse for wear, but are enthusiastically producing seeds nonetheless.
WWC has been working with TACF on pathogen research for nearly 30 years due to the abundance of a specific soil pathogen called Phytophthora, otherwise known as root rot. TACF researchers are using the unique conditions of the WWC ecosystem to study the effects of both root rot and chestnut blight.
Eric Griffin, professor of ecological forestry in the environmental studies department, said that chestnut blight is an invasive species likely introduced when a Chinese chestnut tree was brought to New York.
“I know that this soil pathogen is really prevalent [in] most places and it's a generalist, so while the chestnut blight only causes disease on the American chestnut, the Phytophthora soil pathogen causes root rot in 300 species in the forest,” Griffin said.
It is important to have American chestnut trees that can resist both pathogens.
Chestnut trees were a vital part of the pre-colonial ecosystem of North Carolina and towered above the other trees in the canopy. Their spiky seed pods protect their namesake: the highly nutritious chestnut. The loss of chestnut trees has irreparably changed the ecosystem and affected plants, animals, humans and more who relied on them.
“You know, there were over three billion trees that were lost because of this blight,” Griffith said. “And Jared Westbrook, who was actually one of the science directors at the TACF says that it would take [roughly] two thousand years, even if we were able to breed a highly resistant tree species with either the hybridizing or the transgenic kind of operation. It would take hundreds or thousands of years to restore those trees to the abundance that they had prior to the blight infection.”
To combat root rot and blight, TACF is breeding and genetically crossing the American chestnut with Chinese and Japanese chestnut varieties which are more resistant to both pathogens. However, the goal of these hybrids is for the trees to remain as close to a fully American chestnut as possible so as to not affect the environment in unexpected ways.
On Thursday, Feb. 29, TACF and WWC’s Forestry Crew will be working together from 8:30 a.m. to 11:30 a.m. to plant new Chestnut seedlings for study.
“If students are interested in coming up for that, I'm happy to have them,” Griffin said. “I am particularly interested. We have students that are doing their Natural Science Undergraduate Research Sequence (NSURS) projects on that work. Nadia Keller is one of [them]. I advise her on her research project, and she is managing this overall effort and monitoring the Phytophthora — the soil pathogen — as well as a part of this project. And so it's it's great and ripe for student research and for potential in-service projects.”
WWC’s chestnut orchard may look unassuming now, but it is evidence of years of devotion from across the country to revitalize an incredible species. TACF collects the seeds from the two mature trees to be saved and potentially spread in the future. And if you look closely at the bark on the trunk, you can see telltale rust-orange scars that show how the trees have survived the blight.
“Forestry stuff is a long-time endeavor,” Griffin said. “A lot of times it takes many decades for things to happen. So please come back and see the orchard because it will hopefully look a lot different in many years with some healthy adult trees.”