Efforts underway to bring the American chestnut tree back from virtual extinction

Posted at 11:20 AM, Dec 26, 2022

BIDDEFORD, Maine — At one time, it was one of the most important trees in American culture. Still, after being wiped out by a fungal blight at the turn of the 20th century, the American chestnut tree has essentially gone extinct.

But inside a greenhouse in Biddeford, Maine, efforts are underway to bring back this tree which once covered 200 million acres of forest across the Eastern half of the United States.

"It was really the most important lumber tree in the 1800s," explained Thomas Klak, a professor at the University of New England.

There were once more than 4 billion American chestnuts in this country. Now they're essentially nonexistent.

For years, Klak and his students have been working to genetically modify saplings to be resistant to that devastating blight that came over from Europe. More than a decade of research is finally starting to pay off as the American chestnut is staging a comeback.

"All evidence suggests we’re on our way," Klak said.

A large part of what they’re doing here is centered around pollen. No place else in the world has this much American chestnut tree pollen stored. The hope is that once they get approval from the U.S. Department of Agriculture, this team will be able to send genetically modified pollen across the country to repopulate these trees.

An approval would be great news for the environment at a time when climate change is only getting worse.

"They’re a really good carbon sequestration tree. They can take a lot of carbon out of the air in a short time," Klak said.

There are larger implications for all of this research. Klak believes the success they’ve seen here in genetically modifying the American chestnut tree could serve as a roadmap to save other trees, like ash trees currently being devastated by the emerald ash borer.

"We have a lot of negative environmental news. If we can have positive news, that’s exciting to be part of," Klak said.