Forests in the West used to be a lot more open, so wildfires were much less severe. How do we know? By looking at tree rings! We can actually see scars from old wildfires in cross-sections like this one. By cross-dating fire scars from multiple trees, scientists can reconstruct what past forests looked like including how dense forests were. (Forest Service video by Erika Reiter)

Near the community of Red Feather Lakes, Colorado, the forest smells faintly of vanilla from the red-barked ponderosa pines and the lingering smokey ash from trees burned in the last round of prescribed burns. Walking through the open forest, Matt Champa, a fuels planner for the Arapaho and Roosevelt National Forests and Pawnee National Grasslands, explains why managing forests for fire is a year-round job.

“No matter the month or the year, we have to be preparing these forests for the next fire,” he says. “We do it step by step by step. And the latest science helps guide us.”

The forest around him offers a simple visual comparison. The untreated forests are crowded with trees, fallen logs, thick brush and shrubs. In contrast, the Magic Feather project area, a patch of forest that has been thinned and deliberately burned, feels and looks different. It is more open, with healthier and larger ponderosa pines spaced far enough apart to let sunlight reach the ground. Champa and his colleague, Wes Page, the forest prescribed fire specialist and former researcher, say these differences matter when a wildfire starts. Page points to how these treatments performed during the 2020 Cameron Peak Fire, the largest wildfire in Colorado history.

“We were able to get firefighters into units that had been treated earlier to start suppression operations,” he says. “These treatments won’t stop a wildfire in its tracks, but they give firefighters safer options and help slow fire spread.”

Building one treatment while thinking about the next

To understand why Magic Feather looks so different, you have to look back more than a decade. In 2012, the Forest Service thinned smaller and mid-size trees and removed some of the dead standing trees. The goal was to remove “ladder fuels” -- shrubs, low branches and small trees that allow flames to climb into the tops of large trees. This is where fires become most difficult to control and most dangerous. After thinning, the logs that were removed were hauled to mills, and leftover branches and debris were piled and burned in the winter of 2014.

Nearly a decade later, in fall 2023, the Forest Service returned to Magic Feather with a prescribed burn. Brush, seedlings and needles that had collected on the forest floor were burned up by these flames. The initial thinning ensured that the prescribed fire did its job without climbing into the treetops.
“With the initial thinning, we were removing the materials that can facilitate a surface fire to transition into the upper canopy of the forest,” explains Mike Battaglia, a research forester with the Forest Service. “Thinning helps reset forest structure so prescribed or natural fire can burn in less intense ways.”

Battaglia has spent decades studying dry Western forests like those around Red Feather Lakes. He was part of a team of scientists who helped reconstruct what these forests looked like in the past and how they burned before modern fire suppression. This detective work about forests of the past was used to create a guiding framework for forest restoration treatments in Colorado Front Range forests. 
“Forests like those in Magic Feather used to sometimes burn at low severity and at other times had patches that burned with enough intensity to kill some of the older, larger trees. This fire pattern created a forest that not only is open but also has alternating openings and clumps of trees,” says Battaglia.

Forest Service researcher Mike Battaglia points to past fire scars on a ‘tree cookie’ (right hand photo). By cross-dating fire scars from multiple trees, scientists can reconstruct what past forests looked like including how dense forests were. (Forest Service photo by Erika Reiter)

Today, scientists and foresters try to mimic those natural patterns. Much like doctors write prescriptions to help you feel better, foresters write “treatment prescriptions” for each project area.

“In the past we did lighter thinning,” Champa says. “Now we understand we can do heavier thinning and still make the forest look more like it did 100 years ago, while also making it more resilient to fire in the future.”

Page agrees: “The science is clear that these forest types are most in need of treatments.”

A thriving forest even with wildfire

Other forest treatment insights from Forest Service researchers are helping Champa, Page and the Forest Service think about how to manage these forests. The National Fire and Fire Surrogate Study, a 12-site project started in 1998 to understand how thinning and prescribed fire work together, changed the common thinking. Justin Crotteau, a Forest Service researcher in Montana, describes the main insight from the long-running study as the “alchemy of addition.”

Matt Champa, a fuels manager with the Arapaho and Roosevelt National Forest, stands in the Magic Feather treatment unit. Magic Feather will likely need to be broadcast prescribed burned again in 15-20 years to maintain it’s open and healthy condition, once new trees grow back into the forest and needles and other fuels on the forest floor accumulate. (Forest Service photo by Nehalem Clark)

“This work was needed because there were so few examples of the long-term effects of these common forest treatment types,” says Crotteau. “Thinning and prescribed fire used together maximize resilience in many Western forests." The combination of thinning and prescribed burning not only reduces the fuels that make wildfires severe but also helps forests resist bark beetles and restores more open habitat for wildlife.

But Crotteau cautions that resilience after treatments does not last forever. After all, forests keep growing.

“The effectiveness of these treatments in protecting forest resources from damaging fire declines over time,” he says.

In ponderosa pine and similar dry forests in the West, the necessary cycle of re-treating could be anywhere from every five to 25 years.

Another major source of evidence comes from a large scientific review led by Forest Service researcher Kim Davis. She and six colleagues examined 40 studies spanning 30 years to understand how thinning and prescribed fire affect wildfire severity. Their results showed clear patterns: forests that were thinned and then burned had wildfire severity reduced by an average of 72 percent. In comparison, forests that were only thinned saw severity reduced by 27 percent.

“This is because prescribed burning after a thinning reduces surface fuels like needles, sticks, and small trees and shrubs that increase fire intensity,” explains Davis. Each of these treatments has benefits, but the combination produces the strongest results.

There’s no last step

As Champa and Page finish walking through the Magic Feather project area, they talk about what comes next. The forest, despite being healthy and open, will eventually need another prescribed burn, likely in 15 to 20 years. 

For now, though, Magic Feather stands as an example of what science-led forest management can accomplish. This area supports all the benefits a healthy forest has to offer: wildlife, hiking, clean water and much more. And when the next wildfire comes, not only will firefighters have a safer place to work, but the Forest Service is also ensuring these forests can be here for the next generation.

In western forests, multiple treatments are often needed to return forests to healthier conditions, more resilient to wildfire. New research explains why. (Forest Service video)