California’s ‘New Normal’ is Dry as Drought-Like Conditions Kill Trees at Critical Levels
Despite California’s record-breaking rains last winter, persistent drier-than-normal conditions across the state have caused millions of trees to die off at unprecedented levels.
David Simmons, Southern California Edison Vegetation and Forestry manager, says there are more dead trees in the state — 27 million just last year — due to various environmental changes.
“The problem continues to get worse because of a lack of moisture, but also a contributing factor is the dense tree population in most of the forested areas,” he said.
Simmons and his vegetation management team help determine if a dead, dying, diseased or otherwise hazardous tree is a safety concern and could impact power lines serving electricity to thousands of customers. If the tree poses a threat, it’s removed right away.

INFOGRAPHIC: LAWRENCE TSUEI
On average, about 40,000 dead, dying or diseased trees affected by drier-than-normal conditions are removed each year and this number has increased in recent years. Many of the trees are located in the mountain communities of Los Angeles, Santa Barbara, San Bernardino, Riverside, Kern, Fresno and Tulare counties. This is in addition to the cities of Ventura, Valencia, Victorville, Covina and Monrovia.
SCE also inspects 900,000 trees across its service territory and crews trim about 690,000 trees annually to meet federal and state regulations. Additionally, numerous trees outside SCE’s designated trimming zones are frequently monitored since they could be a potential safety hazard to power lines.
A handful of those trees were located on Lee Kinzy’s property and at his neighbor’s home in Fresno County where SCE crews examined and removed five dead trees.
“They worked very hard at cleaning up all of the mess that was left behind, they left everything in tip-top shape,” he said.
Recently, SCE arborists began using a specialized crane — called a spider lift — mainly in the Sierra National Forest. The crane is used to help remove dead trees more safely and efficiently. It also helps the crews navigate through challenging spaces in the woods.
“These cranes are really small and compact, they will fit through tight areas which allows SCE cutting crews to remove the trees in a safer manner,” said Simmons. “They lift workers 70 to 90 feet in the air to complete their work.”

The orange dots represent vegetation that may require routine maintenance based on their proximity to conductors and predicted growth rates. Purple dots represent vegetation that has the potential to fall within 10 feet of the conductors and will be evaluated for risk factors.
SCE also uses high-tech equipment known as LiDAR (Light Detection and Ranging) which helps vegetation management crews determine if certain trees could impact electrical conductors on transmission lines and become an electrical hazard. LiDAR is attached to an aircraft and uses laser pulses to measure the distance between objects on the ground.
“LiDAR allows SCE inspectors to see what cannot be seen with the naked eye,” said Seth Reid, an SCE technical specialist, who analyzes the LiDAR data.
Simmons encourages customers to closely monitor their trees, particularly if they’re close to a power line.
“If they see a tree leaning or they feel it’s a threat to SCE facilities, please don’t hesitate to call right away,” he said.
To schedule a tree inspection, to determine if it’s a safety hazard, please call SCE at 800-611-1911.