Forest's fiery plans might fizzle out

But it was supplanted by snow.

Regardless of whether the precipitation has been liquid or frozen, there’s simply been too much moisture during April for Lewis and other U.S. Forest Service officials to begin their ambitious plans for prescribed burning on parts of the Wallowa-Whitman National Forest.

“Right now it’s just too wet,” Lewis said on Tuesday morning, April 26.

He’s an assistant fire management officer for the Wallowa-Whitman’s Burnt Powder Fire Zone, in the fuels division.

Given ideal conditions, forest managers had hoped to light controlled fires on several thousand acres around the south end of the forest, including in the Sumpter and Whitney valley areas and in the southern Wallowas around Balm Creek Reservoir, Lily White and Sparta Butte.

Conditions have not been ideal.

Far closer to the opposite, in fact.

But it didn’t start that way.

Lewis said that in early April, with the snow line receding and generally dry weather persisting, a trend that lasted much of the winter, conditions in some places were almost suitable for prescribed burning.

If the rain had held off for another three or four days, Lewis said burning likely would have started in a few places.

But then one storm dampened the rapidly drying woods.

And the parade of Pacific tempests has continued, with relatively brief intermissions, ever since.

Much too brief to get forests “back in prescription,” as Lewis puts it.

What he means is a piece of ground that’s not so dry that flames will spread too fast or burn too hot, but also not so soggy as to quickly squelch the flames.

The period when a section of forest meets the necessary criteria typically happens only during spring or fall.

In some seasons it doesn’t happen at all.

And Lewis is starting to think spring 2022 might be one of those.

Steven Cooke, Lewis’ counterpart on the Wallowa-Whitman’s Grande Ronde Fire Zone, which generally coincides with the La Grande Ranger District, agrees.

“It’s going to be a really short window (for prescribed burning) if we even get one,” Cooke said on Tuesday, April 26.

As of that day, the Blue Mountain Interagency Dispatch Center in La Grande, which covers the Wallowa-Whitman and parts of the Umatilla National Forest, reported no prescribed burning projects completed this year.

“Right now it’s not looking good for any prescribed burning this spring,” Lewis said. “We’ll see what the rest of the spring brings.”

If it continues to bring frequent rain and snow for much longer, he said the Wallowa-Whitman’s burning “window” might well close at least until the autumn rains (which tend not to be as reliable as those of spring).

As May progresses, fire managers have another criterion to add to their list — conifer trees sprouting fresh green buds.

Once those buds begin to proliferate, prescribed burning is more risky because the flames and heat can scorch the new growth and stunt the tree, Lewis said.

By late May, prescribed burning typically isn’t feasible even if the ground has the proper moisture content. The growth of lush new grass — which is likely after a prolonged period of rain — also can stymie fire managers, since green vegetation doesn’t burn as readily as the desiccated mat of pine needles and other debris that predominates earlier in the spring.

As of now, Lewis said, it would likely take 10 to 14 days of dry weather to get forests to a condition where prescribed burning could be effective.

But for much of April there hasn’t been more than a few consecutive dry days.

That’s not nearly long enough to dry the ground, Lewis said — especially ground that was covered with half a foot of soggy spring snow.

That was the situation with many of the places where prescribed fires were planned this spring, he said.

Snow, as you might expect, poses a more formidable impediment to burning than rain does.

Rain mainly soaks into the ground, and a couple of sunny, warm days can pretty much erase the effects of a rainstorm, Lewis said.

But once the snow melts, the ground remains about as wet as it would be after a rain shower, so the drying cycle is proportionately longer.

“It just really set us back,” Lewis said of the multiple snowstorms in the Blue Mountains during April.

He said some units near Sparta, and a couple on the east side of Black Mountain, south of Phillips Reservoir, are the most likely candidates for potential prescribed burning this spring.

Cooke said a couple units north of Interstate 84 at Hilgard possibly could dry out early enough to be burned this spring, but the potential effects of smoke, given the proximity to La Grande, could be a challenge.

A much different spring

If all the potential burning is postponed this spring, it wouldn’t be the first time, Lewis said.

But this year demonstrates how dramatically different successive years can be.

Last spring was much more conducive to prescribed fire.

In mid April 2021, crews from the Wallowa-Whitman burned several hundred acres of ponderosa pine forest near Phillips Reservoir, about 17 miles southwest of Baker City.

Although a few patches of snow still survived in sheltered spots, Lewis said the lack of spring rain, and the ongoing effects of drought, left the forest floor dry enough to sustain flames.

Those blazes killed a small percentage of pines, and blackened the bark and turned the green needles red on some others.

But Wallowa-Whitman officials, including Lewis, who toured the burned areas a few months later were satisfied with the results.

Forest managers prescribe controlled fires for multiple reasons and in multiple situations.

But the common goal is to reduce the amount of combustible stuff on the ground — dead dry grass, mats of pine needles and fallen twigs and limbs, as well as the manmade debris left after logging or thinning of trees too small to be sawed into boards.

Trimming the volume of this material — what fire officials simply call “fuel” — can curb the risk of wildfires during the summer, when flames tend to be much more difficult to control due to hot, dry weather.

Forest Service officials also say that prescribed fires can spur the growth of native grasses and shrubs that are valuable food sources for wildlife and cattle.

In general, prescribed fires are intended to mimic fires that used to burn relatively frequently in areas where ponderosa pine was the dominant species — every decade or so, according to scientists who have studied fire scars on old growth trees.

Some of those fires were ignited by lightning.

Native Americans also used prescribed fire to partially clear the ground.

Effects on wildfire risk this summer

The ample moisture during April likely will have the predictable effect of pushing back the onset of fire season, Lewis said.

But another effect might not be as obvious, nor is it necessarily beneficial.

The damp spring probably will nourish a bumper crop of grasses — the same grass that would stifle a prescribed fire, he said.

The trouble is that come summer, those grasses almost certainly will turn brown and dry, turning into tinder that ignites about as easily as old paper.

That tinder — what fire managers call “fine fuels” to distinguish them from, say, fallen logs or thick limbs — also can contribute to a fire’s rapid spread, Lewis said.

Ultimately, though, the factor that tends to define how severe the fire season is in Northeastern Oregon is one that can’t be predicted in advance with anything like the confidence of estimating how prolific the year’s grass crop will be.

That factor is lightning.

Those bolts from the sky spark about 80% of the fires, in an average year, on the Wallowa-Whitman and on other public lands in Northeastern Oregon.

(Human-caused fires tend to be more common on private lands.)

Even during severe drought years, the fire season in Northeastern Oregon can be tranquil if lightning is either rare, or it is accompanied by heavy rain that either douses the fire altogether or stifles its spread long enough that firefighters can control it.

That was the case in both 2020 and 2021, when fire danger reached extreme levels in the region, but there were few large blazes.