Prescribed fire across from Aspen Mountain started Monday

At 10:30 a.m. on Monday, April 14, helicopter blades began slicing through the air on a grassy field above houses that overlooked Aspen Mountain. 

The blades beat faster and faster until the helicopter lifted off and turned toward the hillside, doing circles above the landscape. Meanwhile, on the ground, White River National Forest crews worked to give the go-ahead for a “test fire” of the “Sunnyside Prescribed Fire” that was scheduled to take place that day.

After a few laps, the helicopter got approval to drop ping pong ball-like capsules filled with potassium permanganate powder, a strong oxidizing agent that would ignite the ground below it. 

The igniters dropped, invisible to observers on the ground, but wisps of smoke began to rise from the hillside below the helicopter. 

As it continued its laps, no longer dropping fire ignition capsules, the smoke grew until the drainage where the fire began to resemble a smoldering volcano with the occasional lick of flame reaching above the terrain.  

After landing and consulting with ground operators, the helicopter would take flight again and drop more flame-igniters and expand the burn to the 900 acres planned, working with firefighters on the ground who were launching flare guns to start fires lower on the hill. 

According to David Boyd, White River National Forest public information officer, prescribed burn operations like these cost around $700 to $1,000 per acre to burn, whereas mechanical operations like cutting down fuel cost $4,000 per acre. Wildfires cost even more, reaching over $10,000 per acre. 

Over the course of the day, the helicopter and about 75 ground-based firefighters and staff would expand the burn, keeping a close eye on its progress, smoke output, wind direction and strength, and a slew of other factors to ensure it burned within control. 

On Saturday, April 12, Eagle County put out a Red Flag warning for high winds and extreme fire conditions. Just two days later, the wind died down enough to proceed with the burn. 

“We only do these projects when the conditions are right,” said Phil Nyland, an Aspen–Sopris Ranger District wildlife biologist. “Sometimes we only get one shot at these things, and a huge measure of success for this project is community support and making sure that firefighters are safe and the public is safe. If we lose those things, then the other things we talk about don’t matter.”

The fire, which is part of the Forest Service’s plan to conduct mitigation on more than 40,000 acres of land from Aspen to Glenwood Springs and slightly beyond, will provide the valley with additional fire mitigated acreage and bolstered biodiversity.

The Red Mountain zone, which was burned primarily on Monday but will be monitored and managed for the next several days, is being burned in a “mosaic” pattern. The pattern will reduce fuel in the area and provide firefighters with prospective break zones to prevent sparks from spreading potential wildfires while also retaining some of the old vegetation. 

Perhaps as important, however, will be the fire’s effects on plant health in the area. 

“Normally, what would happen is lightning would ignite something and this would have burned at some point in the last 100 years,” said Ali Hammond, director of Community Wildlife Resilience for the Aspen Fire Protection District. “But because we have human communities around us, we want to protect those communities by putting out fire as much as possible.”

Because those natural fires are put out, older brush grows higher and gets to a stage where it stops contributing new, nutrient-rich resources to the environment.

According to Nyland, fire mitigation in the form of prescribed burns can be a huge benefit for wildlife in the area. Fires burn old undergrowth that has stopped contributing significantly to soil health in a way that returns much of the nutrients in those plants back to the ground. 

Controlled fires are significantly colder in temperature than wildfires and, as a result, leave a lot of the carbon from the undergrowth without burning essential root structures deep in the ground. 

Nyland said those roots will immediately start shooting up new growth since, in controlled burns like the Sunnyside burn, those root structures are left intact.

Additionally, this new growth gives deer, elk, and other animals new and more accessible sources of nutrition. Often the old growth brush that was in the area grows high enough that elk and deer can no longer reach the new growth, where a majority of the nutrients are held.

In the case of the Sunnyside fire, it can be beneficial to still leave some amount of that old growth behind to provide cover for large game traveling through the area, as well as for migratory birds, insects, and other animals. This is part of why the rangers are burning the Sunnyside area with a “mosaic” pattern as opposed to burning out the entire hillside. 

“The mosaic retains some of that existing vegetation that may not be great forage, but it does provide cover for elk and mule deer, but also provides song birds with nesting habitat and that type of thing,” said Nyland. “So we’ll retain some of that in the project area right away.”