ON NAMAKAN LAKE — Smoke plumbed upward mixing with clouds and drawing curious boaters to Mica Island last week.

The popping noise of balsam fir trees catching fire could be heard from the water and a smell often associated with campfires filled the air.

The fire was set intentionally July 19 as part of a two-day prescribed burn on six islands in Voyageurs National Park.

Reasons to  burn

Prescribed burns are conducted throughout the country for fire prevention and plant restoration. Fire destroys fuels on the ground that could burn out of control in the event of human-caused fire or lightning strikes.

Last week’s burn was done later in the year than typical burns, said Terry Severson, fire management officer stationed at VNP and also the burn boss for last week’s burn. And the park had never conducted a burn on islands, he said.

Typically, prescribed burns are conducted in the spring because of weather conditions. However, this burn was a attempt to lengthen the burn season, Severson said. Spring conditions can suddenly change to become too dry and hot to burn, he said. If the conditions change, prescribed burns can no longer be conducted.

A fire in Voyageurs in 2004 and the Ham Lake fire along the Gunflint Trail shows the need for prescribed burns, he said.

“It’s a fire-dependent ecosystem,” Severson said. “The Ham Lake fire really drives home the fact that we need to use fire as a resource.”

Last week’s fire helps restore the ecology of the island to a more natural balance by reducing the amount of balsam fir on the island, said Scott Weyenberg, the fire ecologist stationed at VNP.

The balsam fir competes with red and white pine seedlings for sunlight on the islands. In addition, the fire is expected to generate pine seedlings.

“In restoration, we’re removing some of the things that are shading (the more desirable species),”  Weyenberg said.

Balsam fir is also fuel for wildfires, Weyenberg said.

Another intended benefit of the prescribed burn was to protect Kettle Falls, which is located northeast of the island complex, Weyenberg said. Forest fires usually burn from south to northeast, he said.

The intensity of a wildfire is expected to be reduced with the removal of balsam through a prescribed burn. A lower intensity fire is easier to extinguish, Weyenberg said.

In addition, last week’s fire will help the park determine how artifacts in the park will react to fire. An archeological fire study was conducted in which six plots of artifacts were set up on two of the islands by an archeologist three months ago. During the prescribed burn, the fire crew burned the plots using three ignition techniques.

Overall the burn went well and the crew continues to monitor the islands, Severson said.

International fire

Harold Boven, a fire management supervisor with the Ontario Ministry of Natural Resources, spent part of a day last week viewing the prescribed burns.

A discussion on conducting a prescribed burn over the international border between Minnesota and Ontario is in the beginning stages. An international prescribed burn has never been conducted before, Severson said.

An international prescribed burn is a long-term objective, Boven said. The Ontario MNR and VNP have a mutual interest in prescribed burns involving white pine, he said. An agreement is in place that allows the two countries to share expertise and resources during fires that cross the border, Severson said.

Perfect conditions

Many factors must be considered prior to a prescribed burn, which VNP typically conducts once a year, said Weyenberg.

The decision to proceed with a prescribed burn is based on the Canadian Forest Fire Behavior Prediction System. The system makes calculations based on current and past weather and then estimates the fire danger, Weyenberg said. The estimate includes how dry the brush is and how fast a fire would run.

A test burn on a small area is conducted before the prescribed burn to consider how the fire will react, Weyenberg said.

If temperatures are too hot or the fire isn’t reacting the way the fire crew predicted, the prescribed burn is canceled, Weyenberg said.

Out of control

A burn boss hopes to have a boring burn — meaning that all goes as planned, according Severson. A contingency plan is in place even before the prescribed burn is lit, in an effort to be prepared should a fire get out of control.

Control lines — paths cleared of much of the vegetation — outlining the planned burn area are established before the fire is started. If a fire crosses a line the on-site crew has set up, crews seek swampy or lowland areas to create another control line. If the fire continues to move in an unintended direction, the Minnesota Department of Natural Resources is called in for additional resources.

As a part of last week’s burn, a medical plan was established that includes the phone numbers for ambulance services and air evacuations and the travel time to hospitals and medical centers.