National Geographic - UK (2022-05)

GARTH LENZ

Forest scientists are
struggling to figure
out a response to
“sudden aspen decline,”

as they call the die-

offs that have struck

since the turn of the

century. But they know

drought and rising

temperatures make

the trees more suscep-

tible to disease and

insects—such as the

tent caterpillars that

defoliated this stand.

CANADA

GRANDE PRAIRIE, ALBERTA

QUAKING ASPEN,

NORTH AMERICA’S MOST

WIDESPREAD TREE,

IS DYING IN DROVES