The deadly experiment that could save the American elm

After more than a decade of nurturing, it had come time to infect this 28-acre grove of American elms with a disease that would almost certainly kill them. Dressed in hunter-green muck boots, grey pants, and a brown Nature Conservancy T-shirt, Gus Goodwin knelt down to give the first tree its shot. Using a bamboo stake marked at 12 inches as a gauge, he measured that far off the ground, held his drill at a slight downward angle, and pulled the trigger.

“We need to create a wound,” Goodwin, the conservancy’s director of science and technology advancement in Vermont, said as the tool began to whir. He bore an inch-deep hole into the tree, the bit sending shavings spiraling out behind it. Putting the drill aside, he took a blue pipette from his tool box and injected 2 teaspoons of a clear solution containing roughly 100,000 spores of the fungus that causes Dutch elm disease.

“That’s it,” he said. “Pretty simple.”

One by one, row by row, the plan was to stick nearly all of the 5,300 or so elms at the sprawling site in southern Vermont, save the few that received a squirt of water as a control. In the coming weeks, most of the trees would doubtlessly succumb to the pathogen that has already killed tens of millions of their ancestors and made Ulmus americana an endangered species. The ones that live, however, could help save the species.

A research specialist with the University of Vermont records information young elm trees that have been inoculated with Dutch elm disease on May 19, 2026. Jessica Rinaldi / The Boston Globe via Getty Images

This project is the most promising attempt yet in the decades-long effort to restore a crumbling pillar of American forests. If successful, it could spawn the largest, healthiest, most genetically diverse population of disease-tolerant elms North America has seen in more than a century. Those trees would provide shade and elegance wherever they cast shadows and support the creatures, like double-toothed prominent moths, specifica…