Found: One Oak Tree, Famously Missing

Instead, the group hopes to propagate or graft small sprouts they found at the base of the tree, and protect those offshoots in living collections at arboretums or botanical gardens. “That is going to be our insurance policy against extinction,” said Murphy Westwood, vice president of science and conservation at the Morton Arboretum, a partner of the project. Down the line, Knapp said, cultivated clones could be potentially transplanted back into the wild.

The surviving tree’s infertility is a reminder of the precariousness of species whose existence is limited to a solitary, imperiled population. Rediscovery was just step one. Bringing it back from the brink is the next. “We’ve been given that second chance, and we just can’t blow it,” Eason said. “It’s not one we’re going to waste.”

Researchers at Morton will also continue an ongoing molecular audit to confirm whether the DNA from the discovered tree matches previous Q. tardifolia samples from herbariums. The genetic work will also aim to settle long-standing debate over whether Q. tardifolia is a distinct species in its own right or a genetic blur between two other hybridizing oaks.