U of I researcher gets closer to creating a new tool for rangelands

In September 2024, a wildfire blazed through 4,500 acres of University of Idaho’s premier rangeland research facility, Rinker Rock Creek Ranch (RRCR), including both the land and a portion of its infrastructure at the cow camp. The fire was fully extinguished in five days but, by that time, had burned through an additional 3,000 acres of adjoining lands near Bellevue.

Leland Bennion, a U of I researcher and restoration ecologist, was hired by U of I in partnership with The Nature Conservancy to assess how pre-fire land management affected the severity of the fire.

“Pretty frequently, there’s very limited data on the condition of the land before and after a fire,” Bennion said. “When the fire happened at Rinker, it was a great opportunity to relate information we already had on the management of the ranch with effects of the burn.”

At RRCR, pre-fire management included cattle grazing and the installation of in-stream structures within water channels. Cattle grazing reduces the density of highly flammable fuels like grasses and shrubs while in-stream structures increase the ability of the stream to meander and thus recharge existing groundwater reserves, allowing the dirt above-ground to retain its moisture and mitigate the fire.

Bennion’s research aims to determine how Rinker’s land management practices altered the effects of the fire, which could inform future management in rangeland systems in the West. The research also focused on evaluating pre-existing burn severity metrics, which are tools used by ecologists to determine the burn severity of an area. They are largely divided into field-based assessments or remotely-sensed satellite methods.

Burn severity is a term used by ecologists to describe the amount of ecological change, such as a loss of biomass, that occurs within an environment due to a fire. For example, the loss of biomass that occurs if a sagebrush-dominated landscape is replaced by cheatgrass after a fire would impact burn severity.

“Another big part of this project was determining whether or not existing burn severity metrics performed well in rangeland ecosystems, since they’re primarily developed for the forests of the American West,” Bennion said. “Unfortunately, we found that they don’t gather the information necessary to accurately represent burn severity on rangelands.”

For instance, Bennion conducted some analyses of fires archived in the federal database of wildfire where he compared the given burn severity measurement with one produced using satellite imagery and field assessments. He discovered that not only were the results inconsistent, but they completely ignored the survivorship of perennial grasses, which are one of the main drivers of wildfires within rangelands.

This discovery led Bennion to co-author a paper with representatives from several land management agencies in the West that argues for the development of better, more accurate burn severity measurement tools and decision-making protocols for rangelands.

“Ideally, a burn severity tool would provide land managers with information about which areas of the fire are most in need of rapid intervention in terms of ecological restoration,” Bennion said. “This will then allow funds and resources to be streamlined into those areas.”  

Though the new tool is still in the ideation stage, Bennion hopes it will link samples collected by researchers on the ground with remotely-sensed satellite imagery. For him, the ideal situation would be to release this tool — as well as the research findings that guided him — in 2027.  

“The idea is that we would take aerial imagery of a post-fire environment and classify that imagery in a way that we feel best resembles the severity of a fire based on observations made on the ground,” Bennion said. “But some of these fires are hundreds of thousands of acres, so we need to be able to increase the scale of our understanding from the ground level to what’s going on across the entire landscape.”

After working with RRCR staff and U of I researchers for nearly a year, Bennion looks forward to continuing his research where it all started.  

“I was born and raised in Boise but lived elsewhere for about a decade. Right after earning my doctorate, previous colleagues kept telling about this position at Rinker, and I couldn’t help but think that this was the perfect opportunity for me,” he said.

As he works to develop a new burn severity tool at RRCR, Bennion keeps U of I’s land-grant mission at the forefront of his research, along with other U of I colleagues.  

“It’s been really nice to work with a group of people that are passionate about what they do, which I think is really important,” Bennion said. “This group really embodies the values of a land-grand institution, which revolves around a mission to serve the citizens in every county of Idaho.”