Every spring farmers and ranchers intentionally burn their fields to jumpstart the natural process of renewal. But those fires can be dangerous. That’s why researchers in Nebraska are designing a new drone to start fires, which may help protect people and the environment.
On a warm spring morning, a big burn crew dressed in yellow and green flame-resistant clothing gets ready to set 26 acres of tallgrass prairie on fire at Homestead National Monument of America near Beatrice, Neb.
Mark Engler, park superintendent, said today’s prescribed burn is special. A team from the University of Nebraska-Lincoln is trying out a new tool: a fire-starting drone.
“Introducing this technology is an important step forward for us in testing new methods to work, not only prescribed fires but really, wildland fires,” Engler said.
The burn team starts lighting the edge of the prairie with drip torches—basically big gas cans with a wick. As firefighters walk along the growing flames, UNL Computer Science professor Sebastian Elbaum gets the drone ready to launch. He described the burn plan:
“Once they build this horseshoe-shape black area [of burned grass], we’re going to have our drones there fly across this field and drop some of these balls that will ignite into flame,” Elbaum said. The idea is to “help them perform the task that [the firefighters] right at the center are performing right now, which can get risky if the wind changes or if they get caught up in there.”
Once the drone is airborne, it drops ping-pong balls filled with a flammable fluid into the unburned area in the middle of the field. In less than a minute, the chemical reaction inside sets the balls on fire. UNL’s NIMBUS Lab adapted this firefighting technology—already used with helicopters—to work on a drone. DiracTwidwell, a UNL agronomy and horticulture professor who studies fire ecology, is part of the fire drone team.
“Fire has been historically so important to keeping our prairies healthy, and managing for the biological diversity that is endemic to Nebraska and elsewhere in the Great Plains,” Twidwell said.
Fire reduces plant litter, helps seeds germinate and keeps invasive plants and trees—like eastern red cedar—out of grasslands. Twidwell said fire plays a big role in agricultural productivity of the plains.
“Our grassland species are becoming increasingly more rare and threatened; we’re starting to see more endangered species pop up. We have an 80 percent loss of livestock productivity on our native rangelands when we see things like cedar overtake them,” Twidwell said.
Getting rid of cedar trees is why farmer and rancher Mark Alberts started burning his land fifteen years ago. He’s burn boss for the Central Platte Rangeland Alliance, a collection of landowners that help each other burn fields and pastures in central Nebraska. His group does big prescribed burns—800 acres on average—often in cedar-filled canyon country.
“It's rough,” Alberts said. “It's very rough terrain, very rugged.”
Alberts said he would definitely be interested in using a drone in those rugged areas normally set aflame by guys carrying drip torches on foot or riding ATVs.
“The drones being able to drop fire in those inaccessible areas…it’s much safer,” Alberts said.
Other farmers that burn small, flat fields say they may not need the technology. But Alberts said he’s interested in using the drone as a camera, too.
“Sometimes, our burn will be two miles, two square-miles, and you just can't see – the terrain is so rugged you just can't see from one end to the other,” Alberts said. “So if you had eyes in the sky that would be great.”
Casey McCoy, acting fire program leader for the Nebraska Forest Service, said he thinks the drone has a lot of potential to improve the safety of prescribed fire. And that could save lives.
“We've had a fairly challenging track record here in Nebraska. The last five to six years we've had a number of fatalities associated with prescribed fires,” McCoy said.
Burn bosses say the drone won’t remove the need for human firefighters, and they’d invest in other essential equipment—like water tenders—before a drone. Still, technology to keep humans out of harms’ way may become part of a firefighter’s—or rancher’s—toolkit in the future.
