This grass burns Utah’s valleys

Invasive grass species such as cheatgrass fuel wildland fires in Utah’s valleys and foothills. Here’s what’s being done to stop them and how you can help.

(Rick Egan | The Salt Lake Tribune)Cheat grass grows at the site of the Dry Canyon fire in Lindon, on Friday, Oct. 1, 2021.

This story is part of The Salt Lake Tribune’s ongoing commitment to identify solutions to Utah’s biggest challenges through the work of the Innovation Lab.

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It only takes a spark. A dramatic bolt from the sky or an ember drifting silently from a campfire could end in thousands of acres of burnt wildland.

For the Range Fire, which burned 3,500 acres near Dry Canyon in Lindon in 2020, it began with a stray round at the Orem Police Gun Range.

“We grabbed dinner and we just sat and watched it,” said Tara Bishop, a research ecologist with the National Forest Service. “It burned everything you see here,” she said, taking in the mouth of Dry Canyon and nearby foothills with a sweeping gesture.

“Ignition starts a fire, yes,” said Bishop, “but where the fire goes from there — how long and how far and how fast it burns — depends on the fuel.”

(Rick Egan | The Salt Lake Tribune) Tara Bishop from the National Forest Service, talks about the cheat grass at the site of the Dry Canyon fire in Lindon, on Friday, Oct. 1, 2021.

Utah has plenty of fuel.

Invasive grass species have overwhelmed Utah’s desert ecosystems, filling in nearly every available gap in the sage along the foothills of the Wasatch Front. The most aggressive of these, cheatgrass, is so widespread in Utah that most people don’t even recognize it when they look at it.

“This time of year when you look up at the foothills and see that fuzzy yellow-brown all over them,” said Bishop, “Yeah, that’s cheatgrass.”

Decades of effort by the forest service, conservation scientists and others have failed to find a silver bullet to defeat this surprisingly short and unassuming invader. Meanwhile, cheatgrass marches on, spreading with human development and drawing strength from climate change.

“The valley bottoms should burn every 1 in 300 years, or so,” said Matt Madsen, an associate professor of plant and wildlife sciences at BYU. “And now cheatgrass is coming in and they’re burning much more frequently. Every 5 or 10 years in some places.”

If we are to have a future in the hot, parched years to come, experts argue, we must find a way to address the dry and crackling fuel that surrounds us.

The Invader

“Is that it?”


It took a good 20 minutes before I felt sure I knew which was cheatgrass.

Standing at the mouth of Dry Canyon, Tara Bishop, who works with the Forest Service’s program on Maintaining Resilient Dryland Ecosystems, continually pointed at it and I repeatedly failed to see it.

“Cheatgrass is very plastic,” she said, “meaning it adapts easily. Where it has space it grows taller and where it’s more crowded it stays short.”

Dry Canyon is “crowded” and the sample she plucked for me (so I couldn’t miss it) was only 6 inches tall.

(Rick Egan | The Salt Lake Tribune) Tara Bishop from the National Forest Service, holds some cheat grass at the site of the dry canyon fire in Lindon, on Friday, Oct. 1, 2021.

Cheatgrass likely found its way from the Mediterranean to Utah about a century ago, mixed in with grain seed, probably wheat. By the 1970s and 80s, scientists began to note its invasive presence in the arid west. By then, it was firmly entrenched along the Wasatch Front and other wildland-urban interface areas.

“There are estimates that more than 96% of exotic species introductions fail to take hold in new environments,” said Bishop.

So why, then, did cheatgrass succeed?

Bishop offers several reasons:

  1. Cheatgrass doesn’t skimp. A single plant may produce between 25 and 5,000 seeds. “The seed banks are unreal,” said Bishop, “they can last two to three years.”

  2. Cheatgrass loves water. “It steals available water so that even if you seed an area with native seeds, cheatgrass will win.”

  3. Cheatgrass starts early. Considered a winter grass, it evolved to capitalize on water early in the year. “Whereas our native perennial grasses have their own internal clocks timed to let them grow at the right time so they won’t germinate too early and die over winter,” said Bishop. “Cheatgrass doesn’t care about that, it just grows.”

  4. Cheatgrass wins with climate change. “It’s not so much the amount of water that matters as the timing,” said Bishop. Those native species with their clocks set for summer rain are not prepared for these changes, while, “winters with more rain and less snow help cheatgrass.” It also benefits from human disturbance. As human development spreads further and further out into the “sagebrush sea,” we break up the biologically active soil, giving cheatgrass places to take root.

  5. Cheatgrass cheats. “In dry years it hugs up against native shrubs like sage brush for shelter, then in wet years it races out and gobbles up all the space it can.”

The result? Utah’s valleys and benches are covered in a prolific winter grass that dies off early and then “waits for a spark,” said Bishop.

Fighting back

On July 6, 2007, lightning struck outside of Milford, Utah, igniting what would become the largest wildfire in Utah history. The Milford Flat Fire burned over 363,000 acres in just over a week.

Visiting Milford in 2021, I was struck by the odd lack of native sage brush, pinyon and juniper.

Matt Madsen of BYU’s Seed Technology Lab was not surprised when I shared the observation, adding, “after a large wildfire, like the Milford Flat Fire, it can take over 100 years or more before sagebrush moves down to the middle of the burned areas.”

Cheatgrass and other invasive grasses serve as the leading fuel for fires in Utah’s valleys and foothills, say Bishop and Madsen.

Losing thousands of acres of sage in a week has consequences beyond poor air quality and dangers to homes, farms and ranches. There are more than 350 plant and animals species in decline from the loss of sagebrush.

The most notable is the Utah sage-grouse population which has long danced with possible listing as an endangered species.

“When a species gets listed, then it affects the rancher, too,” said Madsen, “and the local person that wants to go ride their mountain bike through that area.”

The U.S. Forest Service and conservation scientists have been trying to beat back cheatgrass for decades. From controlled fire to fungus, they have tried it all with little success.

(Jim Urquhart | Tribune file photo) In this July 2007 file photo, fire from the nearing Milford Flat wildfire closes in on traffic on Interstate 15 near Cove Fort.

Madsen and his students hope they have the solution. After a wildfire, it is vital to get native and locally adapted perennial grasses and shrubs to grow. Yet even fire is unlikely to kill off the cheatgrass seed beds.

The application of pre-emergent herbicide is seen as one solution to give desert plants a chance, but of course it kills native seeds too.

Madsen’s team has developed an activated charcoal seed coating that neutralizes the herbicide around native and perennial seeds, allowing them to emerge as winners in the struggle with cheatgrass.

Tara Bishop isn’t fond of the idea of using herbicides,“but I’ve been using it this year and it works,” she said. She will use whatever reasonable tools she can find in the fight against cheatgrass.

“Our desert ecosystem doesn’t get the respect it deserves. It’s a huge carbon sink, it’s fragile and beautiful and it’s our home.”


Solutions in practice

Dr. Tara Bishop notes that human-caused wildfires have been down this year due to an increased attention to fire hazards. “It proves that if we try to be careful, we can actually prevent fires,” she said.

Here are a few tips for preventing grassy fires:

  • Be careful when parking your car on the side of the road or in areas with high grasses, keep your tailpipe away from grass. Heat alone is enough to ignite cheatgrass.

  • Take your vehicle in for regular tune-ups, and practice proper maintenance. Remember that the Parleys canyon fire was started by a faulty catalytic converter.

  • When in wilderness areas stay on designated trails. Straying may break up biologically active soil, creating room for cheatgrass to invade.