Gov. Jerry Brown has declared a state of emergency to help California address a bark beetle infestation that is killing tens of millions of trees, including many in Inland forests.

The governor sent a letter Friday, Oct. 30, to U.S. Agriculture Secretary Tom Vilsack seeking federal action for “the worst epidemic of tree mortality in its modern history.”

The tree die-off is exacerbated by four years of extreme drought conditions, which has left trees vulnerable to the native beetles.

The United States Forest Service estimates that more than 22 million trees have already died in California. Brown is asking the federal government for additional funding and help for private landowners to remove dead and dying trees.

A U.S. Forest Service survey released earlier this year found than 2 million trees have died in Southern California, half of them in the Los Padres National Forest north of Los Angeles, and that bark beetles are present in those forests.

The survey described a situation similar to what was seen in 2002, when the last drought triggered a massive die-off of Ponderosa, Jeffrey and other pines. That was a year before the devastating Old Fire ripped through 91,000 acres of dry and dead trees in the San Bernardino National Forests, destroying almost 1,000 homes and causing eight deaths.

Following the 2003 fires, the Forest Service began a massive effort to thin the San Bernardino National Forest. For years, contractors thinned stands of trees and cleared brush and dead wood. Officials say the forest is healthier than it was a decade ago.

The beetle problem in Southern California is not as severe as the rest of the state.

Tom Scott, a natural resources specialist based in Riverside for the UC Cooperative, said he expects trees in Southern California forests to fare better with the bark beetle infestations because they benefited from some unusual rain this storms summer.

Some forests in the region got as much as four inches of summer rain, allowing drought-parched trees to hang on until more rains follow because of the storm-producing El Nino system over the Pacific Ocean.

“Because of these rains, many of trees were able to recharge themselves,” Scott said. “But anywhere north of Santa Barbara, and certainly the Sierra Nevada, it is still very dry.”

Scott added the policy makers should also address land-use policies that allow people to build in forested areas that are likely to burn.

Removing dead trees may have environmental consequences because dead wood enhances habitat for many species of plants and animals.

Brian Nowicki of the Center for Biological Diversity said Brown is conflating dead trees with wildfire risk when there isn’t a clear connection. He said maintaining forests for wildlife habitat is crucial in dealing with the effects of climate change.

“This oversimplifies a process and a look at the forest that could confound meaningful ways to manage our forests,” Nowicki said.

The national conservation group also questioned the need to suspend state environmental laws, which require public input.

Under Brown’s proclamation, the state authorizes agencies to contract more with wood-burning power plants to generate electricity and suspends the competitive bidding process.

— Staff Writer David Danelski contributed to this Associated Press report.

Contact the writer: 951-368-9471 or ddanelski@pe.com