Wildfires scorched a vast swath of the American wilderness last year. But whether the 10 million acres that burned is a record, as the Obama administration recently announced, or an exaggeration, as some environmentalists claim, is a source of heated debate in a long-running fight over how to manage the nation's forests.
A network of about 30 small environmental groups that view wildfires as a natural part of the ecology - and think more should be allowed to burn -- consider the U.S. Forest Service's record declaration a scare tactic. These critics say the service suppresses too many fires as part of what Chad Hanson, a fire ecologist for the John Muir Project, calls "a 19th century notion that they damage the ecology and are bad."
The dispute could have ramifications on Capitol Hill and for communities surrounded by wilderness and the firefighters who defend them. The Agriculture Department, which controls the Forest Service, spent $1.7 billion battling last year's blazes and is pressing lawmakers to provide more funding this year. Climate change has extended the fire season, officials say, and more huge fires are likely given the ongoing drought in the West.
But the critics want Congress to deny the request, saying the way the service manages the woods - with logging contractors cutting trees and removing underbrush - is actually causing more intense and damaging fires. Hanson and fire historians say that in the early 20th century, up to 30 million acres burned each year, mostly in the understory of trees and with less severity.
"Over a dozen years of scientific inquiry tells us that increasing logging, especially the clear cutting and intensive thinning operations" proposed in Agriculture's request for more funding, "would damage habitat, threaten species," the groups wrote in a letter to senators last month.
Much of their concern is focused on what the service does after a fire, when it clears charred trees and other debris to prevent it from reigniting. They say birds and small mammals use those damaged trees as habitat, and new plants thrive again within a few years.
Fires are "necessary and important for our forest ecosystems . . . and should not be universally extinguished at great cost to taxpayers," the groups wrote.
But the environmental community itself is divided over the issue. Nearly 150 larger organizations sent their own letter to Congress in November supporting the Forest Service. They said the agency is responding to wilderness and an ecology that has changed dramatically in the past 50 years. Millions of acres of wildlands that once burned routinely have given way to homes and businesses, something the service must consider, they noted.
"We need to have intelligent fire fighting," said Chris Topik, director of the Restoring America's Forests program at the Nature Conservancy, which signed onto the November letter. More than half of new homes built since the 1990s are on the edge of wild land, he said. "The essence is, there's so many more people at risk. There are things we all really care about, like wilderness and wildlife, but you have to gauge it with the risks."
Moreover, the drinking water for millions of Americans comes from rivers and streams that are often filled with soot and eroded debris after fires - another reason the Forest Service says cleanup is important.
Criticism of the service's methods is not new, and officials dismiss the accusation that 2015 was not an unprecedented year, saying that the way wildfires are measured now is far superior to the haphazard record-keeping of the past.
The National Interagency Fire Center relies on state and federal agencies across the country as part of a coordinated system that did not exist before 1960. Satellite and laser mapping are used in the effort.
"We're not arguing about fire, we're arguing about forest management," said Agriculture Undersecretary Robert Bonnie, who oversees the Forest Service. "Public lands management is not without controversy."
Thomas Swetnam, a professor emeritus at the University of Arizona who studies wildfires, says comparing those from the early and mid-1900s to ones today is like comparing "apples and oranges." Back then, Gulf Coast states such as Florida, Alabama and Mississippi regularly set massive fires in a forest ecosystem that stretched over 90 million acres; officials believed it should be cleared for various reasons, including as a preemptive measure.
Those intentional blazes were once included in the Forest Service's historical tally, but no longer. The statistics posted online by the interagency center - the ones used to mark 10,125,149 acres burned in 2015 as a record - only go back 55 years.
Yet a more important change, Swetnam said, is the change in fire geography and behavior. The big fires are primarily breaking out in the West, and they're more frequent, hotter and bigger, something he links to warming temperatures.
"What's been happening in the last 30 years is absolutely unprecedented in the western U.S.," he said, adding by email, "The trend(s) . . . are genuine, and very damaging and worrisome."
But the Forest Service is also to blame, said Terry Davis, director of the Mother Lode chapter of the Sierra Club, which encompasses 24 Northern California counties. Before the 1960s - before the service started removing brush and charred trees to try to prevent future occurrences - most wildfires in his neck of the woods tended to be low-severity burns that simmered in the underbrush, he said.
"Now the trend after fire suppression is (that) half of fires are high severity," he said. "Instead of having a nice burn that eliminated fuels, they climb up to the top of trees and crown."
Davis sees fires as instrumental, even necessary, in shaping forests: "The dry Western forests like we have in California evolve with frequent fire."