In 2020, the Grizzly Creek Fire burned 32,631 acres in Glenwood Canyon, which led to massive debris flows on the burn scar the following year. Five years later, land managers are still monitoring the area, which has seen significant regrowth and recovery.
Ryan Sparhawk, a soils scientist for the White River National Forest, is showing me some oak brush trees near the trailhead of the Grizzly Creek Trail. It runs along Grizzly Creek in Glenwood Canyon, and most of it is still closed due to damage sustained during the 2021 mudslides.
“So here's a good example of where a tree, an oak brush, has been burnt and had died off above the surface,” he says, moving branches aside so we can get a better look. “And you can see, still, residual burn scars at the base, the blackening of the base of this.”
“But there's also all this new regrowth that has happened all around it,” he said.
Sparhawk was one of the first people on the scene after the Grizzly Creek Fire. He helps the forest do Burned Area Emergency Response, or BAER reports, and Grizzly Creek was his first one.
“And my initial reaction to this, not having experienced wildfire before, was, ‘oh my goodness, you know, this is apocalyptic looking,’” he recounted.
Since then, he’s been monitoring the burned area and doing targeted restoration work in some of the areas that were more severely burned. His assessment today?
“The fire recovery is… really looking good,” he said enthusiastically.
How severely a fire burns the soil impacts nearly every phase of recovery after the fact. That’s why Sparhawk says BAER reports always start with an overview of where the fire damaged the soils the most.
“Then we share that with our hydrologists, (who) can do modeling for larger rain events,” he explained. “Then that falls into the aquatics resources. Like, ‘well, if we're gonna have these large events, are those gonna affect our streams and water quality?’ Then engineers can start looking at that information for roads.”
Recovery in Glenwood Canyon hasn’t been without its challenges. For one, most of the severely burnt areas were located very high up, on top of the canyon, which was a logistical challenge for Sparhawk.
“In the Blue Gulch drainage, I found 300 acres that we could access using helicopters,” he gave as one example. “And we applied a wood mulch to help with surface erosion.”
There were also, of course, historic rains in 2021 which sent debris flows down into the canyon, closing Interstate 70 for weeks. As part of the BAER report, Sparhawk and his colleagues created various models to see how different parts of the burned area may experience erosion, based on both burned severity and the amount of rain. The 2021 mudslides were triggered by severe rains that some experts called a “500-year weather event.” Sparhawk says they didn’t model for rain that intense.
“It exceeded the water holding capacity of our soils,” Sparhawk said of the rain. “So the soils were not able to absorb as much water that fell. Even in the low burn severity, moderate burn severity areas, there would still be runoff.”
And climate change is altering the landscape. This summer, much of Northwestern Colorado experienced very severe drought, and Sparhawk says that’s part of a trend.
“There's been a steady decrease in soil moisture over about the last 15 years across the forest,” he said.
Colorado’s historic 2020 fire season
Grizzly Creek was just one of many ignitions that occurred during Colorado’s 2020 wildfire season. That includes the state’s three largest wildfires on record: Cameron Peak, East Troublesome, and Pine Gulch. Like Grizzly Creek, they burned later in the summer and into fall, following a year of drought and early runoff.
Camille Stevens-Rumann, an associate professor of forest and rangeland stewardship at Colorado State University, said climate change is driving these droughts, and that creates the perfect storm for fires.
“One of the things that really strongly is linked to bad fire seasons is early snow pack melt, right?” she said. “And we know that that's happening as we warm even slightly. Basically, even if your fire is in September, those fuels have been dry for three months instead of one.”
Stevens-Rumann, who is also the director of the Colorado Forest Restoration Institute, said in addition to fires themselves, climate change also impacts decisions land managers make about post-fire recovery.
“I think on the climate side, we need to figure out if a place is still suitable for, say, the same trees that were there pre-fire,” she said. “And there are some places that perhaps aren’t… It might not be the same forest that we thought of it being before.”
In Glenwood Canyon, natural regeneration answered that question for Sparhawk and his colleagues. In places where there were once dense stands of pine, creating thick canopy cover, there are now aspen trees.
“Within the first year, I witnessed three to four feet of new growth on some of these aspen trees,” he said. “So it was really fascinating to see how quickly they were able to establish in some of these high-burn severity areas.”
Sparhawk is pleased to see more diversity—and hopefully—more resilience in the post-fire landscape. Aspen trees thrive after fire-related disturbances on a landscape, and preliminary research from Western Colorado University indicates that fires can act as barriers to fires spreading.
Of course, all that revegetation and recovery starts with the soil.
“Soil is the basis for everything. Soil's the best,” Sparhawk said, laughing.
Copyright 2025 Rocky Mountain Community Radio. This story was shared via Rocky Mountain Community Radio, a network of public media stations in Colorado, Wyoming, Utah, and New Mexico, including Aspen Public Radio.
