The fire blazes through the prairie field, burning the grass and shrubs in its way.

Is it a wild fire? A malicious prank?

No. It’s a weed management method.

Every year, park officials around the U.S. employ this method, called controlled burn or prescribed burn, to get rid of invasive alien plants and help native plants thrive.

With the help of professional fire experts, park officials did controlled burns of parts of Stony Creek Metropark on Thursday, April 1, to kill off an invasive alien plant called autumn olive. 

“If we did nothing at all, in four, five years, this would just be a shrub field,” said Paul Muelle, chief of natural resources at the Huron-Clinton Metroparks, which manages Stony Creek and 12 other metroparks. “All this grass would eventually disappear.”

Autumn olives are a big problem in many parks in Michigan, and parks try to manage these plants so that the native flora can flourish.

“There’s so much of it that we have a hard time keeping up with it,” Muelle said.

Other methods of managing the autumn olive situation include mowing the field, pulling out the plants and spreading herbicide, but Muelle said the more effective method is mowing down the field and burning it the next year.

Many measurements are taken to ensure safety. Before doing a prescribed burn, officials must inform law enforcement officials. They also take weather readings, and if the conditions aren’t favorable, the burn is delayed.

If it’s too windy, they don’t do a burn because the wind could carry the fire to where officials can’t control it.

He said fields usually go through a three to five year burn rotation.

“We’ll leave this field alone now for another three or four years, take a look at it, and if it needs it, we’ll come through and put fire across it again,” he said.