Thursday, December 01, 2011
Red-headed woodpeckers cackled above as they flitted between white oaks, distracted as they were from gorging on this year's bumper acorn crop by the huge plume of smoke and small flames down below. It's the most wonderful time of the year, fall fire season! when all of that preparation of firelines really pays off. Today was no exception.
We're in maintenance mode here in the Niangua Basin unit, an area that's been burned for the past 30 years. The fire program started in this tract of woodlands when I was walking door to door selling Girl Scout cookies. Today's weather conditions were ideal: no frost on the windshield, winds 5-8 mph, relative humidity between 21-32% all day. It's a rare occasion to actually burn woodlands in the Ozarks when the threat of a cold front presses. When frontal systems move in they're usually accompanied by squirrely winds shifting directions and sometimes of high intensity. A quick call to Springfield NOAA this morning revealed that the cold front wasn't going to reach the Western Ozarks until around 5, with winds shifting to the North at 2-3 mph. No real threat there, since the fire will be finished by around 4 with an ignition time of 10:30 am. Be wary of burning on the same day a frontal system is expected.
Fire crept along the toeslope, barely moving. We kept at it, sending strips of fire into the woodlands, walking well into the unit with fire, dripping streams of it at the base of hills in hopes of an upslope run here and there. The fire continued to creep. We kept walking, dripping fire. As I walked through one patch of aromatic sumac with my lit torch, a red bat flew up out of the leaf litter, so close in front of me I saw his charming facial features and the venation pattern on his large, almost translucent pink wings. He was tangled in the brush, in the sumac, but he quickly fanagled himself free to perch in a nearby post oak. Red bats are not only fire tolerant, sensing smoke and fire that trigger them to fly up to a nearby tree to wait for the flaming front to pass, but they're fire dependent: in a recent study, it was discovered that red bats only exist in woodlands that are burned every 3-7 years. Unburned woodlands in the study harbored no red bats. Red bats can't exist in thick, overstocked woodlands. They need fire.
I thought a lot today about a diversity in fire regimes when implementing prescribed fire. In papers and presentations, I often talk about how important it is to change the seasons of fire, the frequency of fire, the intensity of fire. Today, only a few days after a decent enough rain the Niangua Basin, fire intensity was pretty low. Today's fire was the definitive "low intensity, frequent fires" that shaped much of the Ozarks. We didn't need to restore the woodlands here, they were restored 30 years ago when the fire regimes that existed in the Niangua Basin for the past 5,000 years were returned to the scene following active fire suppression since the 1920s.
Today's plodding little fire coursed through the whole 250 acre area. Around 3:30, as the shadows grew long and the deep muck fen (with Carex buxbaumii, no less) burned completely, we met up with the other crew. Fire behavior was simple, and our beautifully formed smoke column could be seen clearly from Westphalia. We stripped the interior, setting all the grass on fire, and walked the beautifully prepared firelines twice to make sure no snags were compromising the line (but they weren't because the awesome fire crew blew out around them...), to make sure the fire continued over the hill to the other hill, through the drainage, through the fen. A classic example of a low intensity fire today, a fire that consumed leaf litter, maybe knocked back some brush but not all, in a burn unit that will be a showcase in April, rich with morels and wildflowers and red bats and woodpeckers.
Posted by Allison Vaughn at 6:26 PM