For the second straight year, the federal government has run through its budget for fighting wildfires amid a grueling, deadly season and will be forced to move $600 million from other funds, some of which help prevent fires.

This year’s budget depletion reflects the new normal in firefighting, where parched seasons last at least two months longer than in previous decades and wildfires burn bigger and hotter, according to the U.S. Forest Service and conservationists who track fires.

More than 31,900 fires have burned 3 million acres in the United States this year, according to the Forest Service.

Compared with other fire seasons in the past decade, that is mild. Last year produced the
second-worst season on record: 67,700 fires burned 9.3 million acres, according to the National Interagency Fire Center. In 2006, more than 96,300 fires burned 9.8 million acres.

A total burn of 5 million acres was once a rarity in fire seasons that ran from June to September before 2001. But since then, the season has expanded from May to October, as a changing climate has brought longer stretches of dryness and drought, providing fires more fuel to burn.

In an Aug. 16 letter to regional foresters, station directors and deputy chiefs, Forest Service Fire Chief Thomas L. Tidwell said this year’s depletion of funds was predicted, “and we must now transfer funds from other accounts to make up the difference.”

Tidwell issued several directives, telling subordinates to immediately defer awarding contracts for everything except the removal of hazardous fuels and emergencies, travel only when absolutely necessary, and cut back on hiring and overtime pay.

Reducing Forest Service funding affects rural economies, where the agency pays contractors to remove trees and brush, and other operations such as logging.

“I recognize that this direction will have significant effects on the public, whom we serve, and on our many valuable partners,” as well as on the agency’s ability to manage forests, Tidwell said. “I regret that we have to take this action and fully understand that it only increases costs and reduces efficiency.”

As of Monday, the Forest Service had spent $967 million to pay for firefighters and the equipment that supports them. That included more than $200 million in the congressional Federal Land Assistance, Management and Enhancement supplemental account known as FLAME.

That left only $50 million to control at least 40 fires burning hundreds of thousands of acres in Idaho, Oregon, California, Utah, Nevada, Wyoming, Montana and other states. President Obama was briefed on fire-control efforts this week, and nearly 18,000 personnel are fighting fires.

California Gov. Jerry Brown (D) on Thursday declared a state of emergency for a wildfire near Yosemite National Park that has burned more than 84 square miles and is only 2 percent contained.

The shelter provides breathable air and some heat and fire protection.;

The Forest Service spends $100 million per week to manage fires when at Preparedness Level 5, its highest state of alert, which it reached Tuesday, a spokesman said. Now the service must borrow from other programs to put them out.

“The Forest Service is making $600 million available for wildfire suppression from other funds,” said spokesman Larry Chambers. “Our goal remains to safely protect communities and ensure the safety of our firefighters.

“We will continue to fund important wildfire activities, and work to minimize the impact to other programs and services,” Chambers said in a statement via e-mail.

But conservationists are deeply worried about how the government has juggled funds in recent years to pay for firefighting.

“We need to get serious about investing in forest restoration efforts that reduce the risk and intensity of fires, and we need a sound disaster funding method that provides emergency responders with the resources they need to protect people, water and wildlife,” said Chris Topik, director of the Nature Conservancy’s Restoring America’s Forests program.

Some environmentalists, as well as Forest Service officials who spoke on the condition of anonymity because of fears about losing their jobs, blame Congress.

Over seven years starting in 2002, the Agriculture Department, which runs the Forest Service, was forced to transfer $2.2 billion from other accounts to fight wildfires when the budget came up short, according to records provided by the Forest Service.

Congress, which sets the budget, at times reimbursed only a fraction of those funds. Last year, lawmakers reimbursed the USDA and the Interior Department, which plays a far lesser role in fighting fires, with $400 million from the 2013 Continuing Resolution after state firefighters and conservationists pushed to save programs that prevent fires.

Topik said the FLAME fund was supposed to erase the need for emergency cash infusions when Congress established it with $415 million in 2010.

In 2011, after the previous year’s mild season, Congress pulled $200 million from the account and placed it in the general fund. The following year resulted in the second-worst wildfire season on record.

A House Appropriations Committee spokeswoman said at the time that its chairman, Rep. Harold Rogers (R-Ky.), and members “believe that providing adequate funding for wildfire suppression is of the utmost importance. This is why they fought for hundreds of millions in funding in recent . . . legislation,” as well as in appropriations bills.

But this year’s budget sequester, forced by Congress, cut more than $115 million set aside for federal wildland fire programs, USDA and Interior officials said.

At a time when the nation faces abnormally dry conditions, particularly in the West, Agriculture Secretary Tom Vilsack and Interior Secretary Sally Jewell were forced to manage burns with 500 fewer firefighters and 50 fewer engines.

“I hope we can get through this fire season without any fatalities,” Vilsack said in May.

A little more than a month later, 19 members of the Granite Mountain Hotshots were killed fighting a blaze that suddenly engulfed them in the Arizona town of Yarnell.

More than 100 homes were destroyed in that fire.