In the middle of the state's drought, many trees aren't getting sufficient water to remain healthy.
Some of them eventually die, or are in the process of dying which sends out a pheromone signal attracting some bad visitors.
Bark Beetles swarm to dying trees and bore holes inside, destroying the little remaining structural integrity the tree has.
In the case the tree is close to a power line, PG&E removes the trees one at a time.
"We don't want them falling on our power lines and taking them down, or starting a fire," said PG&E Vegetation Manager Jeff Mussel.
Thursday in the Meadow View area of Placer County, crews took down the dead and dying trees before they become a fire hazard or fall over completely.
PG&E will remove the tree free of charge if it is your area and threatening a power line.