We are learning more about what is fueling record-breaking Canadian wildfires.
Dry conditions amplified by a lack of normal snowpack and spring rainfall left millions of acres susceptible to fire across the country, but it is a small pest that is also to blame.
Pine bark beetle infestations in forests have left dead trees and combustible residue on the ground. These fires are responsible for the rush of smoke clouds covering skies and sunlight in the U.S.
