By Adrienne Bozic and Chelsea Richardson
On May 23, a lightning strike sparked a wildfire that burned more than 21,000 acres in the eastern Upper Peninsula, the third largest Michigan wildfire in modern history. This fire burned for 20 days before it was considered 100 percent contained.
The toll on local homeowners was devastating; the fire destroyed 136 structures, including 47 homes, a store, and the famous Rainbow Lodge at the mouth of the Two Hearted River. The fire stretched all the way to Lake Superior, almost thirteen miles north of its southern extent. At final tally, the fire burned 21,069 acres, making it the third-largest wildfire in modern Michigan history after the 25,000-acre Mack Lake Fire (1980) and the 72,000-acre Seney Fire (1976).
A total of 300 personnel assisted with the Duck Lake Fire, building 42.6 miles of fire line, almost half of them dug by hand. Cooperating agencies included the Michigan State Police, Luce County Sheriff’s Department, Luce County Emergency Management, Wisconsin DNR, American Red Cross and Salvation Army. Many news reports noted that Luce County and Newberry residents would line the streets in the evening as fire personnel drove home for the night, cheering loudly and holding signs thanking them for their hard work.
Many natural areas in Luce County were affected by the fire, which can have potentially positive ecological responses in fire-adapted ecosystems such as those found in the Duck Lake fire area. Many ecosystems throughout Michigan are fire-dependent and require periodic fire to maintain their specific ecology and function. According to the DNR website, prescribed fire is also used to maintain habitats such as prairies. Many endangered species depend on warm season grasses and prairie remnants for their survival. Fire is also used to maintain large openings and oak savannahs. Savannahs are open, park-like areas with scattered trees. These areas need periodic fires to keep brush and trees from turning them into a forest.
A portion of MNA’s Swamp Lakes Moose Refuge was burned in the Duck Lake fire. On June 26, MNA’s Upper Peninsula Regional Stewardship Organizer Adrienne Bozic visited the sanctuary to survey the fire damage. Approximately 40 acres of the 160-acre sanctuary were affected, mainly along the southern tier of the property. The fire exhibited interesting behavior south of Pike Lake, possibly due to varying forest types present which have differing levels of combustibility and burn at different rates. For example, in Swamp Lakes, the fire abruptly stopped at areas dominated by broad-leaved hardwoods such as maple, which presumably formed a fire break of less-flammable material.
Hardwood trees are denser and will burn at hotter temperatures and a slower pace. Pine, a softwood which contains more resin and less dense features than a hardwood, burns faster. Pine trees also have very dry bark and needles, and the resin of a pine is highly flammable and will burn for a long time due to the all the oils in it. As a result, pines ignite quicker and burn faster. The main species burned by the fire were jack pine with a little red pine. Species that didn’t carry fire well include red maple, sugar maple, birch and beech.
The fire crew used the primary road through the sanctuary as a fire line. Equipment was used to widen the road by approximately 1-2 feet on each side, and to push brush off the road and pile it some distance from the road. It is anticipated that pre- and post-fire activities have likely spread propagules of invasive plant species, and their establishment and spread will be carefully monitored in future years. Special time and attention will be paid these critical first few years post-fire when factors such as recent disturbance, scarified soils, increased sunlight, and a flush of available nutrients make these roads and adjacent forest attractive seedbeds for many species, including aggressive invasive species.
At the sanctuary, bracken fern has already sprung up, carpeting the otherwise blackened landscape. By next spring the forest floor will be thriving with herbaceous plants taking advantage of the flush of nutrients released when the previous forest matter burned. Michigan’s population of Kirtland’s warbler may benefit too, as the bird’s jack pine habitat requires fire to reproduce.
MNA will continue to carefully monitor Swamp Lakes and provide regular updates to members. If you are interested in touring Swamp Lakes to witness the fire damage on September 20, please contact Adrienne Bozic at firstname.lastname@example.org.
For photos from Adrienne’s post-fire visit to Swamp Lakes, see the MNA Flickr page.
[Updated: July 26, 2012, 8:27 a.m.]