Grassland Vs. Timber: How Montana’s East-West Divide Affects Fire Behavior
Wildfires have torched almost 800,000 acres in Montana so far this year. But burns in eastern Montana’s grass and farmland and western Montana’s mountainous, timbered landscape behave very differently. Freddy Monares spoke to MTPR reporter and editor on the podcast Fireline Nick Mott about the different types of fires in Montana.
FREDDY MONARES: Nick, thanks so much for joining us.
NICK MOTT: Thanks for having me, Freddy.
FREDDY: The PF Fire and Richard Spring fires in eastern Montana charred a little more than a quarter of the state’s total burned area. Those stand out to me because they got so big, so fast — but they also seem to have gotten under control pretty quickly. Is that typical for fires on the eastern side of the state?
NICK: It definitely is. I talked with Carl Seielstad, a professor of fire science and management at the University of Montana about this. He also still manages fire so he’s seen a lot of both timber and grass fires on the ground.
He said in general, “If we think about grass fires versus timber fires, grass fires tend to be fast: They start fast, they go fast, they get big fast and they end fast.”
That’s compared to, say, a fire in a forest ecosystem that might simmer for weeks or months before we get cool, wet enough weather for it to go out.
One reason for that difference is when we’re talking about grasses, we’re talking about "flashy fuels."
“Flashy fuels” means thin, flammable stuff like grass. So, a really interesting dynamic of the seasonality of grass fires is that it all depends on precipitation. A really wet period early in the year causes a lot of growth, followed by a long dry spell that could create tons of fuel. And we can also see grass fires in spring and fall, when we don’t usually see fires in the forests.
He told me visually on the ground, just the sight of a fire in grassland is fundamentally different than in a timbered, mountainous landscape — if you’re up high you can see the whole thing. He said one way to think about it is kind of like the difference you might experience in hunting on either side of the state.
"Hunting elk in a timber system where you're creeping along and looking, you know, 40 or 50 yards out is a completely different experience than hunting antelope in eastern Montana where you're looking through your glasses and you can see animals that are miles away. I mean, it's no different with fire," he says.
FREDDY: Forest fires are an important part of the ecosystem. Do grass fires have the same sort of history on the landscape?
NICK: Absolutely they do. If we think historically, Seielstad said the Lewis and Clark expedition actually documented continuous fire from almost North Dakota to the Rocky Mountain Front.
“Fires were vast, beyond comprehension, beyond anything we see today,” Seielstad says.
And the prairie fires we would’ve seen would’ve been across huge swathes of the whole country, not just in Montana.
FREDDY: Is fighting a grass fire any different than fighting a timber fire?
NICK: Yeah, it is — first off, the speed at which grass fires burn can definitely be dangerous. So there are a lot of accidents that happen in grass fires. But some of the basic rules of firefighting are kind of universal. Like, there’s a saying: “Keep one foot in the black,” or the area that’s already burned — that’s so you can get to safety if things get out of hand.
“And that really applies to grass fires where you want to be right on the fire edge, because if the wind changes, you want to be able to step into what's already burned,” Seielstad says.
“Grasses provide a lot of advantages for firefighting.”
There are a lot of strategies that are just more feasible in a landscape that’s more open. The fuel type is pretty homogenous, compared to a mountain ecosystem where you can have really rugged terrain and pretty radical changes in things like tree type and elevation that could affect how things burn.
FREDDY: Let’s talk land ownership. Eastern Montana is so heavily private and agricultural compared to, say, Forest Service land in western Montana. How’s that fit in?
NICK: That’s a huge point. That predominantly private landscape in eastern Montana means livelihood for lots of ranchers out there. So a grass fire, for example, might be directly burning away all the food for a herd of cattle. Seielstad told me he’s heard stories of ranchers trying to get ahead of the flames and clipping fences so their herds can get out of harm’s way.
“Oftentimes the impacts of fire in eastern Montana are really immediate. And really, I mean, it puts you as a livestock owner into crisis mode right away.”
On the other hand, that private ownership means it can be easier to get around out there and there are lots of so-called fuel breaks in the landscape — things like roads that can be a big advantage in fighting a fire. Lots of landowners are also used to putting out small fires on their property. So it’s really a part of life out there.
FREDDY: Let’s go back to the Richard Spring Fire that we started out with. That fire started out from a coal seam, which seems rare and hard to prevent. What sorts of things can be done about that kind of risk?
NICK: That’s a really tricky one. Some solutions could involve better mapping and knowledge of where these could occur. But coal seams can burn for decades underground and there are thousands of abandoned coal mines in Montana. This isn’t a problem unique to this state — resource-rich Western states like Wyoming and Colorado also have had major issues with coal seam fires. A burn called the Coal Seam Fire on the Western slope of Colorado, for example, burned about 30 homes back in 2002.
FREDDY: What should we expect for the remainder of fire season?
NICK: We’re in this cool period with some more moisture right now, which could be good news. But things can change really, really quickly in grassland — and in our forests, the heat and drought we’ve had up till now have left things primed to burn. So it’s possible we still have a long way to go in both parts of the state. But we’ll have to wait and see.
FREDDY: Thanks so much, Nick.
NICK: Thank you, Freddy.
FREDDY: That was MTPR’s Nick Mott talking about different fire types in Montana. You can learn more about wildfire in the west on the podcast Fireline, available on mtpr.org or wherever you get your podcasts.