Prairie Fire Meets Its Match: How BLM Fuels Management Halted the Blaze

On September 17, 2024, a lightning strike ignited the Prairie Fire near the Colorado border in the Cisco Desert of Southeast Utah. Winds quickly spread the fire through grasses and sagebrush, burning approximately 700 acres before encountering an unexpected barrier — the Bitter Creek herbicide treatment area. 

This treatment falls under the BLM’s Fire Program: Hazardous Fuels Management, a key component of the agency’s year-round firefighting efforts. Outside peak fire season, much of the Fire program’s work is focused on hazardous fuels management — strategically managing vegetation to restore ecosystems and reduce spread and intensity of wildfires. 

In 2019, the Bitter Creek aerial herbicide treatment aimed to control the spread of cheatgrass, an invasive species which fuels wildfires and displaces native plants. Native perennial bunch grasses, like galleta grass, grow in clusters, creating gaps between these fine fuels which then helping reduce wildfire spread. These grasses are also "warm season" varieties, meaning they stay greener and retain moisture longer, making them more fire-resistant. In contrast, cheatgrass dries out quickly and forms dense, carpet-like patches which easily ignite and promote the rapid spread of fire. 

The herbicide used was imazapic, a pre-emergent herbicide that prevents the germination of new grass seeds while leaving established plants and most seeds unaffected. 

On the day of the Prairie Fire, strong winds drove the flames north, quickly burning through 500 acres of grass. As the fire advanced, it reached denser vegetation, causing flames to surge over 10 feet high. A road contained the fire on the west side, but on the east, it crossed another road and kept spreading until it reached the Bitter Creek herbicide treatment area, where it ran out of enough continuous vegetation to keep going. 

A post-fire survey found that only 23 percent of the treated area was covered in cheatgrass, compared to a 2023 survey showing 80 percent in the untreated area near the fire perimeter. This highlights the effectiveness of such treatments in protecting both ecosystems and communities from the devastating effects of wildfire. 

Sagebrush ecosystems, like the one impacted by the Prairie Fire, are vital for supporting a wide range of plant and wildlife species. However, they are increasingly at risk due to factors like pinyon-juniper expansion, the spread of cheatgrass, and frequent large wildfires. Restoring and maintaining these landscapes through treatments like those at Bitter Creek are essential for long-term ecosystem health. 

In 2024, wildfires intersected treatment areas 37 times, but in 89 percent of these incidents, the treatment played a significant role in altering the fire's behavior and aiding in control. In Fiscal Year 2024 alone, BLM Utah completed 87,289 acres of hazardous fuels treatment. 

Looking ahead, the Canyon Country District is planning two large-scale reseeding projects this fall, each covering around 2,000 acres. One project will focus on restoring the Prairie Fire burn scar, continuing efforts to rehabilitate the landscape and encourage the return of native plants. 

By strategically managing hazardous fuels, the BLM helps reduce the intensity of wildfires, which not only protects vital sagebrush ecosystems but also helps safeguard human communities from future fire risks.