August 9, 2014

Researcher: New way of burning could benefit Flint Hills ranchers

For many years now, some Wichita residents have choked on smoke coming from the fires deliberately set in late April by Flint Hills cattle ranchers clearing brush and dead grass.

For many years now, some Wichita residents have choked on smoke coming from the fires deliberately set in late April by Flint Hills cattle ranchers clearing brush and dead grass.

And for years, in part because of those fires, Wichita has narrowly avoided federal air quality sanctions that could cost the city and its residents tens of millions of dollars annually.

“We’re just barely squeaking by,” said Tonya Bronleewe, an environmental quality specialist for the city.

She hopes that new research recently announced at Kansas State University – done mostly by a scientist from Towanda named Gene Towne –might give Wichita and other cities downwind from the Flint Hills a break.

The city hopes ranchers take a look at what Towne has found, Bronleewe said.

“When I saw that report, I got real excited,” Bronleewe said.

“Nobody wants those regulations.”

When to burn

Pat Sauble at age 93 still raises cattle in the Flint Hills on the Sauble ranch near Cedar Point, in Chase County.

Ranchers in the Flint Hills view with suspicion any attempt by city or federal officials to curb their annual grassland burns, he said. If not for the burns, the Flint Hills would become a woodland of cedar forest, nearly impenetrable and useless for livestock grazing.

“You hear sometimes that somebody’s worried about protecting the grasshoppers, or the birds,” Sauble said with a laugh. “But if you don’t burn, the whole country will fill up with cedar trees.”

But Towne, a K-State research scientist, says he began to suspect decades ago that his scientist predecessors, including those at K-State, have been steering ranchers wrong on grassland burning – not about the necessity of the burns, but about the timing.

So he began to set fires, an experiment that lasted decades. He burned, then studied how the grass recovered.

He is now sure he has found something important.

For half a century, scientists told ranchers that they needed to burn in the last two weeks of April to get the best benefit of growing fresh grass.

Towne’s conclusion: Whether winter, fall, summer, early spring – it makes no difference. Ranchers don’t lose any weight gain for their cattle.

And weight gain, as both ranchers and scientists know, is the primary reason to burn the grass. Burning removes last year’s dead grass and helps release nutrients into the soil. Cattle grazing on grass grown in a burned patch will gain 32 pounds more in a season than cattle grazing elsewhere.

“And when you think about it, that makes sense,” Sauble said. “If the grass gets hit by lightning, which happens, does it hurt the grass then? No.”

The only downside to what he has found, Towne said, is some criticism based on misunderstanding.

After K-State announced his findings, he heard that there was talk among ranchers that “those idiots are now saying that we have to burn the prairie only in November.”

“We are not saying that,” Towne said. “We’re saying you have the option now to burn any time you want.”

Weak science

The implications of the project are multiple, and important, said Joseph Craine, a K-State research scientist who helped Towne with the project.

It means ranchers could consider varying their burn schedule, a move that possibly would benefit them – and definitely would benefit cities downwind.

“It doesn’t always happen every year … but in many years, people do decide to burn on the same one or two days,” he said.

“It can create problems when everyone burns at the same time.”

The smoke can carry a long way. People can get sick; federal rules about ozone and particles in the air can get violated.

“And that becomes a political issue,” he said.

What Towne did was put together 20 years’ worth of prairie fire data. It was done at K-State’s Konza Prairie Biological Station, thousands of acres of Kansas tallgrass south of Manhattan.

Sections were burned annually, either in fall, winter or spring. Towne studied how the prairie recovered long-term.

What Towne showed, Craine said, is ranchers can spread out the time schedule over the whole year, if they want. Cattle grazing on the land won’t sacrifice any weight gain.

Part of what led Towne to do the project was that he looked up the original research that scientists put together in the 1950s that led them to set a narrow, late-April window for grass burning.

What he saw disappointed him.

“A lot of what (scientists) told ranchers for the last 50 years was based on weak science that frankly would not pass muster for science today,” Towne said.

Scientists have “told ranchers for decades that the only time you should burn the prairie is late April. And we’ve found that’s not true.”

In fact, Towne said, fall or winter burns might help ranchers put more weight on cattle by creating more protein-heavy plants usually incinerated in the late April burns.

Burns in fall or winter would also mean all those birds that lose their nests to fire in late April would get to keep them. Snakes and turtles also would have a better chance of survival.

New knowledge

Ranchers have not been well-served by past science, Towne said.

Part of the reason settlers of European descent found a vast grassland here in the 1800s, he said, was that American Indian hunters burned the prairie every year for thousands of years, knowing that the fires cleared the dead grass and nurtured new green grass.

“It was a way of attracting the bison,” Towne said.

One beneficial side effect of those ancient burns was that the native cedars and other woody plants were kept in check, huddled along creek cut-banks where fire couldn’t get to them as easily.

But settlers stopped the fires and planted windbreaks – and then got told, by scientists in the 1930s, that burning was bad for the prairie.

It wasn’t. Cedar trees began to spread. It wasn’t until the 1950s and 1960s that scientists sanctioned burning again, but only in that narrow, late-April window.

Sauble said some ranchers knew better and burned anyway, even in the 1930s.

“Everybody wrapped their wooden fence posts with gunny sacks and sloshed water on them with buckets after we set fires,” he said.

He’s not sure what other ranchers will think now about burning in months other than April. Some might do it, he said.

Some might not.

He’s suspicious of change, though he doesn’t mind it. One change he saw in 93 years was that the ranchers who burn the grass switched to steel posts many years ago. Nobody has to wrap them in gunny sacks and slosh water, he said.

New knowledge can be a good thing, Sauble said.

“I discovered a long time ago that those steel fence posts can make a real good large-scale barbecue grill,” he said.

Reach Roy Wenzl at 316-268-6219 or Follow him on Twitter: @roywenzl.

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