As forest fire officials continue to contain the Museum Fire’s growth, some mysteries remain, such as how severely the flames burned through the forests of the Dry Lake Hills and what the fire has left behind.
As of Tuesday afternoon, first-hand accounts from firefighters who had traveled in the fire scar have been the main source for knowledge on just how severe the blaze could have burned and what it burned. However, the Burn Area Emergency Response team is finalizing its report Tuesday night and will be able to give more of a sense of how severely the fire burned by Wednesday.
Foresters with the U.S. Forest Service and researchers at Northern Arizona University’s Ecological Restoration Institute are both looking for those answers as they, and the rest of the community, continue to see the remnants of smoke hang in the air above the fire scar. The data will mean different things for local forest thinning efforts, wildlife habitats, post-fire flooding concerns, and hiking and biking trails within the fire scar.
The Museum Fire is 82% contained and has burned 1,961 acres with 448 fire personnel working on the fire lines, according to data from the Southwest Area Incident Management Team on Tuesday night. The fires burned through ponderosa pine and heavy dead and down mixed conifer in the higher elevations.
The management team, which was shipped in to handle the fire July 22, is leaving as the fire personnel work toward achieving full containment. The team released an announcement thanking those who cooperated and helped them during their assignment.
“We are especially grateful for the way the people of Flagstaff and surrounding areas welcomed us into your communities and helped in so many ways to make our jobs easier,” Rich Nieto, incident commander of the team, said in media release.
Amy Waltz, director of science delivery with the Ecological Restoration institute, said their institute does not study all fires, but the Museum Fire is one that caught their eye. Factors like burn size, history of study in the area and existing forest thinning treatments are things that would make their researchers more interested the fire scar.
These are all boxes the Museum Fire checks off, according to Waltz. The Museum Fire's footprint is the first time the Dry Lake Hills area has burned since the U.S. Forest Service began monitoring and tracking fire behavior in 1910, according to Dick Fleishman, a Four Forest Restoration Initiative operations manager. The area also hasn’t seen much prescribed fires due to the steep mountain slopes and rocky terrain, which makes it difficult to navigate.
“That means it’s had 100 years of continued growth and fuel buildup,” Waltz said.
However, different parts of the fire scar were also subject to forest thinning through the Flagstaff Watershed Protection Project (FWPP), a taxpayer-approved forest thinning project to reduce dangers like the ones the Museum Fire is now posing. The areas within the fire scar were thinned on steep slopes by large ground-based machines and others were thinned by helicopter logging operators.
While the fire scar will be able to provide data on how completed FWPP thinning operations worked, the research will be complicated by the fact that forest thinning in the Dry Lake Hills was not entirely completed yet, according to Matt McGrath, Flagstaff District Ranger with the Coconino National Forest.
McGrath placed the thinning operations work at 50 percent completed. While all helicopter logging had been cut and cleared, mechanical operations had cut 297 acres of the 397 acres, but had only cleared logs and pine needles from 66 acres.
It is not clear at this time how many thinning acres were burned by the Museum Fire, and of those acres, how many acres were cleared and how many acres were only cut.
Additionally, two log decks from helicopter logging, including their largest log deck, burned in the Museum Fire, according to McGrath. Their largest log deck would have required 185 truckloads to remove all of the individual downed logs. The second log deck was much smaller, but still would have required 40 truckloads to remove all logs from the area.
Those now-burned decks are two of six on the mountain where the fire burned through the hills.
“Now we need to go back and re-evaluate what was cut, what burned, what didn’t. That's what my folks will be working on here in the near future,” McGrath said.
Once Waltz and the institute’s researchers get into the field, they will be able to gather data to measure if the thinning operations worked to mitigate fire severity in comparison to how fire burned through areas untouched by foresters and natural fire.
The fact that some thinning areas were not considered properly treated will likely affect research findings of forest thinning impacts.
Waltz said the institute has large amounts of data its researchers have gathered from around northern Arizona. In the past, they have evaluated fire events like the San Juan Fire in 2014 that burned over 6,000 acres in the White Mountain Apache Reservation and Apache-Sitgreaves National Forest.
In the San Juan Fire scar, institute researchers found in acreage that had seen forest thinning and prescribed burning, fire was confined to surface fuels, meaning it burned less severely. Areas that had not been thinned but had seen prescribed fire experienced higher tree mortality.
Waltz said she’s eager to get into the field and learn what occurred in the Dry Lake Hills, but also said she has been watching the weather and the fire as both a community member in addition to as a researcher. She hopes the institute’s resources can be used to the benefit of the community.
“The entire town of Flagstaff is really interested in the outcome of this fire,” Waltz said.