National Geographic - UK (2022-05)

The future of the once

magnificent American

chestnut tree may

depend on saplings

like these in a green-

house in Syracuse,

New York. The saplings

have been genetically

modified to resist

a fungus that killed

billions of chestnuts in

the early 20th century.

AMY TOENSING

BY THE TIME 77-year-old Rex Mann was old

enough to work in the forests of Appalachia,

they were full of the dead.

“We called them gray ghosts,” the retired

forester says of the American chestnut trees

scattered throughout his former North Carolina

home and still towering over the forest floors.

They were skeletal remains of majestic trees

that once grew to be as much as 100 feet tall and

10 feet wide. Over the course of the 20th century,

an estimated four billion of them, one-fourth of

the hardwood trees growing in Appalachia, were

killed by an Asian fungus accidentally imported

in the late 19th century. It’s considered one of the

worst environmental disasters to strike North

America—and also a preview.

SCIENTISTS

CAN

CREATE

STURDIER

TREES

BY ALTERING

THEIR

DNA.

THE BIG

QUESTION:

SHOULD

THEY?

The National

Geographic Society,

committed to illuminat-

ing and protecting the

wonder of our world, has

funded Explorer Amy

Toensing’s storytelling

about immigration in

America since 2021.

SOLUTION

BY

SARAH GIBBENS