Long before South Dakota's landscape included neighborhoods, farmland, fences and cattle, annual fires swept through the state's prairie and forest land. Fire was Mother Nature's way of maintaining a healthy ecosystem, explains Tim Bradeen, habitat resource biologist for South Dakota Game, Fish & Parks.
"Fire is Mother Nature's way of revitalizing itself. South Dakota's plant and animal species evolved around fire events. They thrive after a burn," said Bradeen, of why S.D. GF&P utilize prescribed burns to improve habitat for the state's wildlife.
If implemented correctly, prescribed burns rejuvenate the native prairie plant populations by suppressing invasive plants and cleaning up dead refuge, allowing sunlight to reach the native seedbank, says Bradeen.
"Healthy grasslands provide an abundance of food and protective cover which encourage bird, insect and wildlife populations to grow and thrive," Bradeen said.
The word "prescribed" is used to describe this tool because in order for fire to successfully accomplish its task, timing is everything, says Mike Kintigh, Regional Supervisor for S.D.GF&P.
"It is key to burn at the right time of year so that the grass species or the noxious weeds you're trying to control are set back, allowing less competition for the more desirable native species," Kintigh said.
He says one of the best examples of how prescribed burns improve native grasslands is through the control of bromegrass.
An invasive species, bromegrass is an aggressive grass which crowds out native grasses early in the spring and does not provide wildlife cover in the winter.
"It lies down as soon as it gets snowed on. Wildlife, like pheasants and other birds, need grass that stands up, like switchgrass and bluestem, to provide nesting and winter cover. Other wildlife species also see great benefits year round from vibrant stands of native grasses," Kintigh said.
By timing a prescribed burn correctly, Kintigh explains that GF&P is able to suppress bromegrass in early spring, which gives native grasses time to re-establish.
The department also uses prescribed burns to improve habitat in forested areas. When used in timber, prescribed burns prevent over-crowding, clean up the forest floor and open up the pine canopy allowing sun to reach the forest floor, encouraging re-growth of the forest's shrub layer. The shrub layer is home to aspen and berry producing plants like choke cherries and Oregon grape, which provide essential food and cover for deer and other wildlife.
To ensure timing and conditions are what they need to be for a prescribed burn to work, GF&P relies on habitat specialists, like Bradeen, who are trained and understand the science behind fire and its important role in the native ecosystem.
"There is science behind this tool. Many variables are considered and, depending on what our overall objective is, determine what prescription or fire plan will be written," said Bradeen, of the detailed fire plan GF&P develops in coordination with the South Dakota Dept. of Agriculture Wildland Fire Suppression.
Many factors are considered when developing a fire plan says Robert Lehmann, training specialist and prescribed fire coordinator for South Dakota Wildland Suppression.
"When writing the prescription for what we want the fire to accomplish, we consider the fire intensity needed, the terrain of the land, the fuel load and what weather conditions need to be in place to safely accomplish the burn," Lehmann said. "The biggest unknown in any fire is the weather."
Before a prescribed burn, crews ensure that an area to be burned is surrounded by natural or manmade fire barriers - creeks, roads and mown grass lines.
Lehmann says that when conditions meet the fire plan and they are able to implement a prescribed burn, the results are amazing.
"After a prescribed burn, we see excellent results. This ecosystem is made for fire," he said.
Firefighters work closely when doing prescribed burnsWhen GF&P implements prescribed burns, they do so as part of the five-year management plan each property has and budget for this management action as they do any other project. Prescribed fire can be expensive, primarily due to the expenses of insuring the burn does not get out of control. It can cost $50 to $100 per acre.
"When it comes to managing wildlife habitat, though expensive, prescribed fire yields great results," Kintigh said.