The scope of the tree mortality issue sweeping across the region is larger than Tuolumne County can handle on its own, the Board of Supervisors said Tuesday.

Several letters to state and federal lawmakers requesting aid to tackle the problem were unanimously approved by the board at Tuesday's meeting. The board also renewed a local state of emergency declaring that the increasing number of dead or dying trees poses a serious risk to public safety.

"It's important for the public to understand that the magnitude of this problem is such that the county in and of itself is never going to solve it," said District 5 Supervisor Karl Rodefer, adding that other public and private agencies need to take responsibility for removing the dead trees on their land.

About 77 percent of the land in Tuolumne County is owned and managed by public agencies, largely the Stanislaus National Forest and Yosemite National Park.

"This is huge," Rodefer said. "It's going to take cooperation of all those groups out there to make it work."

An estimated 13 million trees have died throughout the southern and central Sierra Nevada as a result of the four-year drought, according to Cal Fire and the U.S. Forest Service.

The types of trees observed as being affected the worst by the drought include ponderosa pine, sugar pine, incense cedar and various types of oaks. Dense stands of conifers weakened by the lack of water are particularly inviting for bark beetle infestation, according to the Forest Service.

Many county residents have reported concerns about the visible increase in dead or dying trees throughout the area, especially near Twain Harte, Groveland and Tuolumne.

County leaders say the problem poses a major threat to the public due to an increased risk of large wildfires and dead trees falling into homes or critical infrastructure, such as power lines, roads and water conveyance systems.

Homeowners are also finding that removing trees from their properties can be a costly process.

District 2 Supervisor Randy Hanvelt said he spoke with a local tree faller that estimated it would cost as much as $30,000 to remove 20 trees in close proximity to a home.

"We need to find ways to cooperate with these people so that if they can take them down, we can help them do that," he said. "We need to streamline any process there is to make it happen."

County Administrator Craig Pedro said a local task force formed recently to come up with ways of addressing the issue has had one meeting.

However, many of the key stakeholders involved in the process have been busy with the Butte Fire in Calaveras County, including representatives from Cal Fire, the California Office of Emergency Services and U.S. Forest Service.

Pedro said he's met with members of the Highway 108 FireSafe Council, Yosemite Foothills FireSafe Council and Southwest Interface Team, who have expressed interest in taking a leadership role in the process.

"Anyone who takes this on as a key leadership role is going to require some staffing to do it," he said. "When I say things like that, I've got to find a way to fund that. We've got to figure out a financial plan to go with it."

The board approved a letter to Gov. Jerry Brown requesting support through the coordination of resources - including California Conservation Corps and prison inmate crews - as well as financial support through various state grants and funds.

Furthermore, the letter to Brown requests assistance in reducing or streamlining regulations, including requirements of the California Environmental Quality Act, timber harvesting permit process and competitive bidding.

Other letters approved Tuesday addressed to Sen. Dianne Feinstein, Sen. Barbara Boxer and Rep. Tom McClintock also request federal aid.

Contact Alex MacLean at amaclean@uniondemocrat.com or 588-4530.

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