Helicopters check for dead trees near power lines in rural north state

Low-flying helicopters are joining the legion of machinery responding to the state’s fourth-year drought.

Helicopters flying at treetop level throughout rural Northern California are checking for dead and dying trees near power lines, where they pose fire hazards.

The aircraft, contracted by Pacific Gas and Electric Co., have found thousands of trees in need of removal or pruning, said Paul Moreno, a spokesman for the utilities company.

Drought has weakened trees throughout the state and left others susceptible to disease or insects.

PG&E has conducted aerial surveys of Shasta and Tehama counties, where foresters determined that about 400 trees are dead or dying near power lines. They found 350 trees in Nevada, Placer and El Dorado counties, Moreno said.

Low-level flights in Mendocino and Lake counties revealed about 260 dead trees. Tree surveillance flights are scheduled this week throughout Plumas County.

After the flights, which are conducted at 200 to 300 feet, foresters hike to the identified trees for a closer inspection. If a forester confirms a tree needs to be removed, PG&E will work with the property owner to schedule a contractor to do so, Moreno said.

The combination of aerial and ground patrols has identified about 4,900 trees in need of removal or pruning. About 31 percent of those trees have since been removed or pruned, Moreno said.

PG&E’s documentation of dead trees in Northern California, limited to those near power lines, adds to research done by the U.S. Forest Service to assess the scope of the toll drought is taking on federal lands across the state. A recent study estimated at least 12.5 million trees in the state’s national forests are dead or succumbing to the drought.

And it will likely get worse, said Jeff Moore, a Forest Service biologist and the agency’s acting regional aerial survey program manager.

“It is almost certain that millions more trees will die over the course of the upcoming summer as the drought situation continues and becomes ever more long term,” he said.

The Forest Service used a fixed-wing aircraft flying at about 1,000 feet to survey forests in Southern and Central California.

After three years of drought and a virtually snowless recent winter, dying trees are adding to the state’s fire danger, Moreno said. Weakened trees and branches can fall into power lines, leading to outages and wildland fires.

PG&E’s aerial patrols are in addition to the company’s annual patrols along power lines to identify trees and vegetation in need of pruning and removal, he said.