At a Glance

A U.S. Forest Service study found that 18 million trees died in California last year.That's a drop from 27 million in 2017 and 62 million in 2016.Prolonged drought, a beetle epidemic and wildfires have claimed most of them.More than 147 million trees have died in the state since 2010.

California lost an additional 18 million trees in 2018, though the pace of tree deaths has slowed, the U.S. Forest Service announced this week.

In 2016, 62 million trees died; in 2017, it was 27 million.

“It is encouraging that the rate of mortality slowed in 2018. However, 18 million trees are an indication that ," Thom Porter, director of California's Department of Forestry and Fire Protection, said in a news release about the study.

A and California's devastating wildfires , the Los Angeles Times reported.

Overall, across 9.7 million acres of federal, state, local and private lands in California since 2010, the year the drought began, the study says.

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The drought's end in 2016 has helped trees better withstand the beetles. Healthier trees can better resist the beetles. Where the trees weren't as healthy, the beetles ravaged them.

"This has been an absolute epidemic in the southern Sierras to the point where there are no trees left," Porter told the Times. "They ran out of trees to eat."

The Camp Fire, the deadliest and most destructive in California history, burns in the hills near Oroville, California, on Nov. 11, 2018. The fire killed 85 people and burned 153,336 acres.

(Justin Sullivan/Getty Images)

Dead and unhealthy trees provide fuel for the wildfires and pose a significant hazard to people and critical infrastructure, the Forest Service said.

California had , according to preliminary numbers from CalFire.

Wildfires killed 100 people in 2018, a spokeswoman for CalFire said Tuesday. Eighty-five of those people died in November in , making it the deadliest fire in state history. It was also the most destructive, claiming nearly 19,000 structures.

Since 2016, federal, state and local partners have cut down 1.5 million dead trees as part of management and restoration plans, the Forest Service said.

The Forest Service restored about 313,000 acres of forest in 2018.

“The Forest Service is focused on increasing the pace and scale of ecological restoration – this includes thinning dense areas to promote healthy forests that are more resilient to wildfires, drought and bark beetle outbreaks," said Randy Moore, Pacific Southwest Region forester for the Forest Service.

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In one of his first acts in office, Gov. Gavin Newsom urged state lawmakers to provide over the next five years.

Porter told the L.A. Times the drop in the number of dead trees doesn't mean the next wildfire season won't be as destructive as 2018's.

"Regardless of rain or shine, we’re going to have large and damaging fires in California," he said.