Steven Potter
Richard Westbury dribbles burning fuel at Edna Taylor Conservation Park for a “prescribed burn.”
Paul Quinlan starts forest fires.
He also burns prairies and areas around marshes.
As conservation resource supervisor for the Madison Parks Division, it’s his job to keep the city’s natural habitats healthy. For that, fire is his “favorite management tool.”
In mid-November, he and three conservation workers set out to stimulate new vegetation growth and eliminate invasive plant species by burning a section of the Asher Woods forest inside Edna Taylor Conservation Park on the city’s southeast side.
After measuring the wind and going over a tactical map that lists the ignition area, projected burn progression, fire break points and preferred wind direction — as well as the nearest emergency medical centers, in case something goes wrong — the crew splits into two.
Heading in opposite directions along the path, each team drives a heavy-duty four-wheeler equipped with a 60-gallon water tank on the back. Before they get too far apart, they stop the vehicles and a crew member gets out, grabbing a large metal canister called a drip torch. Quinlan lights the wick and turns it upside down close to the ground. As he does this, fuel drips through the torch’s looped piping and over the burning wick, dropping small globs of burning fuel onto the ground.
Within seconds, fire spreads, crackling as it consumes dead leaves, small twigs and branches. The crew steps back to survey the low, wide flames and make sure the smoke is getting plenty of lift so as to not be a nuisance to nearby homes, schools and businesses.
Happy with the initial results, the crew spreads the fire in 10- to 20-foot increments, sporadically stopping to watch its progress. The fire spreads at about five feet per minute. It rarely gets more than a foot high and leaves behind a swath of charred, ashy black earth in its wake.
The crackles get louder as the fire spreads through denser material.
Occasionally, the crew members — dressed in yellow, fire-resistant, fleece-like shirts and pants and hard hats — take the drip torch into the burn area to re-ignite spots that went out or to pour the burning fuel in areas thick with debris. They take care to make sure the low-burning fires move quickly around live trees to avoid a bigger fire.
When the fire reaches an area overgrown with the invasive species known as reed canary grass, the flames reach their highest level. Since this grass is still alive and green, a dense, full smoke fills the air when it burns.
Soon after the grassy area is burned through, the two fires have nearly met each other, completing the circle of the planned burn area in about three hours. As the fire dies — having run out of debris — the crew makes sure the fire is out, sometimes spraying water or a special chemical foam.
This will likely be the crew’s last “prescribed burn” of the year. Quinlan prefers the term “prescribed” to the more commonly used “controlled burn.”
“It’s much more than just starting a fire and making sure it doesn’t get out of control,” he says. “[We plan how] the fire will respond to air temperature, humidity, wind and the topography of the land.” Nearby fire departments, schools and residents must also be alerted beforehand.
The technique of setting slow-burning, low-level fires to clear out fallen leaves, dead vegetation and non-native plants is not only quick and cheap, but effective.
Burning off dead and unwanted plants “allows the sun to reach the ground and warm the soil faster next spring, [which] enables seeds to germinate and the seedlings to get established without competition from older plants,” says Quinlan. “It makes it easier for the sun to reach the new growth.”
It’s also an age-old technique. “Native Americans have used fire to manage this landscape since the last ice age,” he says. “This ecosystem was shaped by fire.”
Successive rainless days needed before burning: 3 to 4
Water on-hand: more than 700 gallons (300 each on 2 trucks; 60 each on 2 four-wheelers)
City conservation parks strategically burned: 6
Burns planned this year: 11
Drip torch fuel mix: about a gallon of 4-to-1 diesel/gasoline mix
Editor's note: This article was edited to correct the diesel-to-gasoline ratio used in the drip torch.
