SALEM — It’d be easy to assume the untamed appearance of the West’s inland forests is timeless.

In reality, their current condition is often anything but normal by historic standards.

For many decades, large swaths of these forests have been untouched by wildfire — the driving force that shaped their structure and ecology for millennia.

“Today’s landscape doesn’t function anything like the landscape of 100 or 200 years ago,” said Paul Hessburg, a research landscape ecologist at the U.S. Forest Service.

Without low-intensity fires periodically consuming the grasses, brush and small trees of the West’s dry inland forests, they’re now more densely packed with vegetation that can fuel large wildfires like those that have raged across parts of the Northwest in recent years.

White and grand firs whose growth was typically stifled by frequent fires are now a more prominent component within forest stands, creating a “ladder” for flames to reach the canopy of ponderosa pines.

“Now, these landscapes are much less well-adapted to fire,” Hessburg said. “You take fire out of the system, you radically change many forests fairly quickly. Fire adaptation occurs as a result of allowing frequent fire to occur.”

As a result of long-term fire suppression in the arid West, there will inevitably be more fire in the region’s forests, experts say. Permanently avoiding fire isn’t an option, so foresters must decide whether they’re willing to actively manage it — or leave that process to chance.

The West’s inland forests have experienced a deficit of low- to moderate-intensity fires that clear out the understory and small trees. While forest managers commonly thin forests to prevent more severe fires, some in the environmental community claim the approach is counterproductive and would prefer for the forest’s ecology to regulate itself. Either way, though, forest treatments are unlikely to totally offset the fire deficit’s impacts.

Coming to a forest near you

“Fire and smoke are coming to an area near you,” Hessburg said. “How do you want your fire and smoke?”

Thinning and prescribed burning of dense stands within national forests is the federal government’s main preventive approach to the problem, but even the largest of these projects that span 10,000 acres or more are modest compared to the 160 million acres the U.S. Forest Service manages in the West.

Not only does this work cost a lot of money, but large-scale treatments require extensive planning that must stand up to the scrutiny of lawsuits filed by environmental groups.

Meanwhile, the biomass — fuel — within Western national forests is increasing.

“Every day, the sun comes up and photosynthesis occurs,” said Gregg Riegel, an area ecologist with the agency. “We’re so backlogged, we can’t keep up with it, and it can’t pay its way all the time. There’s no way to catch up with that.”

The conundrum facing managers in the West’s inland forests is a testament to the effectiveness of firefighters, who are able to extinguish the vast majority of wildfires ignited by humans and lightning. In Oregon, for example, 98% of fires are put out before they’ve grown bigger than 10 acres.

Viewed from another perspective, though, that success rate just allows the powder keg of fuel to continue expanding.

“That’s the dilemma. You can stop fire, you can suppress it, but there’s a consequence to that,” said Tom Spies, a retired Forest Service scientist. “We’re not going to get rid of fire. It’s not a good idea to get rid of fire. It’s impossible to get rid of fire.”

Reducing the density of inland forests on a massive scale is beyond human capacity in practical terms, so the alternative is to selectively allow some fires to burn under the right geographic and seasonal circumstances.

“It’s being discussed more and more because we don’t have the resources to thin and prescribe burn our way out of this,” Spies said. “Let’s fight it in a smarter way and in the process let the fire do some of the work for us.”

Impact on agriculture

For farmers and ranchers who live and work near national forests or depend on grazing allotments in them, the threat of wildfires is more than an aesthetic or abstract environmental issue.

For example, a ranch in Montana recently sued the U.S. government, seeking $9 million in damages for a 2017 wildfire that started on national forestland. The complaint accuses the Forest Service of letting the blaze spread through the forest for ecological purposes rather than suppressing it.

Evaluating the potential risks of allowing a wildfire to burn isn’t something that can be done on the fly as the flames are consuming more acreage.

For this reason, forest scientists are exploring the idea of studying the suitability of different areas for managed wildfire ahead of time.

By analyzing such features as terrain, difficulty of firefighting, proximity to civilization and the behavior of past fires, among other factors, scientists are creating “potential operational delineations” to assist with on-the-ground decision-making.

“That informs, whether you have an ignition or several ignitions, how you choose to respond,” said Chris Dunn, a research associate at Oregon State University who’s conducting such analyses with the Forest Service’s wildfire risk management science team.

The goal is “stratifying” the landscape to identify where wildfires can serve an environmentally restorative role without endangering people or property.

“What we’re doing is trying to take some of it off the plate to focus on the areas with the greatest need,” Dunn said.

That way, forest managers can direct their resources toward thinning and fuel treatments in areas where wildfire is too dangerous to use as a management tool.

“If we were able to thin our forests and get them back to historical conditions, the history indicates we’d be more successful at fire suppression,” he said.

‘Fire refugia’

Lessons about “fire refugia” from forest ecologists are likely to assist in planning, as certain landscape features are known to resist severe wildfires or at least slow their progression.

Areas that burn less frequently or severely compared to the surrounding landscape are considered refugia. The implication is that such refugia can be identified as “speed bumps” or barriers in the broader mapping plan.

“They might have a bit of a different beat to them,” said Meg Krawchuk, a forest ecosystems professor at OSU who studies fire refugia. “They don’t necessarily need to be unburned. They’re places that are buffered a bit.”

Refugia aren’t totally impervious the most severe fire conditions, such as those aggravated by raging winds.

Rather, they’re areas where fire behavior is influenced by multiple elements, including their elevation, slope, proximity to water and position relative to the sun. In general, moisture and lower temperatures contribute to more protective microclimates.

“It tells us about places that are naturally slow lanes,” Krawchuk said.

On the other hand, areas that evolved with low or moderately intense fires sweeping through every 20 years or so actually benefited from the flames. Ponderosa pines with thick bark and tall canopies survived the blaze while the nitrogen was released from burned vegetation, enriching the soil.

The charcoal left behind helps vegetation recover after fires, as it’s capable of storing water and nutrients, said Tom DeLuca, professor and director of the forest and conservation experiment station at the University of Montana.

“It has all these beneficial effects without any negative side effects,” DeLuca said of this pyrogenic carbon. “You get this flush of green growth between fires. You have this cycle that works really beautifully when it works in its natural rhythm.”

Native Americans expertly used fires to encourage the growth of plants they harvested for food, while certain birds and other wildlife actually prefer to live among fire-scorched trees, he said. “There are a bunch of species that thrive after fire because of their evolution with fire. Fire suppression definitely hurts species that are fire-dependent.”

While forest scientists and the federal government now recognize the value of fire on the landscape, suppression is still considered necessary by the Forest Service due to fears overstocked stands will cause high-severity blazes that can easily escape control.

“We call that the pucker factor,” said Gregg Riegel, area ecologist with the agency.

With intense fires, the flames can kill the tree canopy and wipe out forest stands that are then replaced by shrub fields, he said. For that reason, thinning and restoration treatments are more common than managed wildfires.

Chainsaw ‘surgery’

“Fire is a blunt instrument and thinning with a chainsaw is surgery,” Riegel said.

However, some in the environmental community claim the Forest Service’s emphasis on thinning — particularly to extract commercial timber — is more motivated by an appetite for generating revenue than preserving the environment.

“That view is more about economics than it is about science,” said Chad Hanson, director and principal ecologist of the John Muir Project of the Earth Island Institute, an environmental nonprofit group.

Thinning trees is actually detrimental to wildfire prevention because smaller vegetation is exposed to more sunlight, spurring the growth of fuels, he said. Dense trees also reduce temperatures and block winds, hindering the spread of fires.

“The more trees you pull out of the forest, typically, the higher and faster the fires burn,” Hanson said.

Focusing the Forest Service’s resources on helping people fire-proof their homes would create more jobs than expensive fire suppression efforts, which should target forests near human communities, he said.

High severity fires have a place in the forest ecology, and the early seral snag habitats they leave behind should actually be considered “ecological treasures,” Hanson said.

The agency should concentrate on managed wildfires in the back country, where they don’t pose a threat to people, and get out of the commercial logging business, he said. “There’s a lot of politics and economics wrapped up in it, which basically perpetuates these 20th century programs, and we need to change that.”

Who prevails in the “dueling science narrative” of active management versus letting nature take its course will result in very different outcomes, said Hessburg, the research landscape ecologist with the Forest Service.

Without treatments, many pine forest stands currently are maladapted to fire and will succumb to large high-severity blazes, he said.

“Some of the changes we really aren’t going to like and we’re going to live with them for generations. What we will notice in 50 years from now is a very different landscape,” Hessburg said. “These are the changes. These are the politics. People need to decide, policy-makers need to decide what they want.”