On a cold, snowy Sunday in late March, a University of Illinois at Chicago biologist, backed by a volunteer crew, set fire to dry vegetation on one of the last surviving patches of virgin prairie in the state.

"If we didnt do it, in the long run, the prairie wouldnt survive," says Dennis Nyberg, associate professor of biological sciences and director of the UIC-owned-and-operated James Woodworth Prairie Preserve in the Chicago suburb of Glenview.

Prairie fire can be as revitalizing as spring rain. It clears away foreign vegetation, releases nutrients for native plants and opens paths of sunshine to sprouts. Centuries ago, when most of Illinois was tallgrass prairie, racing fires that groomed the land for regeneration were common phenomena. Today, less than 1 percent of the states land is defined as prairie, and only a fraction of that has escaped alterations through human activity.

Nyberg has participated in or supervised more than 20 controlled prairie burns in different locations.

"The fire kills the above-ground part of woody vegetation," he says. Woody, as opposed to grass-stemmed plants, can overwhelm a prairie. Fire is a quick and effective control.

If left unchecked, Nyberg says, "thered be an increase in the amount of woody vegetation and in 25 to 30 years, the prairie would probably turn into a shrub thicket. Were not willing to let things go as an experiment to find out if that will happen."

UIC/ Prairie FireAdd One

Vast prairie fires were historically sparked either by lightning or by humans. Nybergs Chicago prairie burns follow strict controls. Burns are scheduled about 36 hours in advance, based largely on weather forecasts.

Ten-foot wide fire-breaks are mowed and raked along the perimeter of the burn area. The prairie grass is set alight upwind, then the fire progresses along a path, leaving in its wake a charred but cleared field. The process takes about an hour. The Illinois Envir
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Contact: Paul Francuch
francuch@uic.edu
312-996-3457
University of Illinois at Chicago
3-Apr-2001