MANHATTAN, Kan., May 31 (UPI) -- If tallgrass prairie goes without fire for too long, it can quickly transition to shrubland and woodland. A new study puts the tipping point at three years without fire.
To maintain the unique ecosystem of the Plains States, ecologists at Kansas State University recommend more prescribed burns.
Analysis of satellite imagery suggests portions of tallgrass prairie that burned every three or four years -- or less frequently -- were the areas most at risk of becoming shrubland.
"In this area, if we completely exclude fire, the landscape can go from tallgrass prairie to a cedar forest in as little as 30 to 40 years," John Briggs, director of the Konza Prairie Biological Station, said in a news release. "Once it gets to that point, we are not confident that fire alone is going to bring that back."
The Konza prairie is a 8,600-acre native tallgrass prairie bioreserve owned and managed by Kansas State and The Nature Conservancy. It is located in the Flint Hills region of northeastern Kansas.
Researchers say prescribed burns are the most economical strategy for preserving the ecosystem, which has shrunk dramatically over the last century. Tallgrass prairie was once expansive and found throughout central North America. Today, only 4 percent of the ecosystem's original footprint remains.
In addition to being a home for a variety of endemic species of plants and animals, it's also acreage uniquely well-suited for ranching. And though fire is the cheapest means of mantaining the land, it does come with consequences -- more smoke and air pollution.
"There is always a conflict to burning," Briggs said. "Most people think that the remaining tallgrass prairie should be a fenced-off preserve."
"They think that it will take care of itself, but this system is fire derived and historically fire maintained. Aside from the sustainable and ecological aspects, it is critical to people's livelihoods and necessary to ranching communities," he added.
Briggs is the co-author of a new study on the future of tallgrass prairie, published this week in the journal Rangeland Ecology and Management.