The air is filled with the sound of sharp popping and the familiar smell of campfires. Nervous laughter skips through the fall air. The scene, however, is not one of a campsite. A group of University of Delaware students is standing at the edge of a field that has just been deliberately set aflame. Workers from Delaware Department of Natural Resources and Environmental Control (DNREC) started the fire. This fire is no accident, however, nor is it a case of government employees turned arsonists. It is a prescribed burn, intended to rid the fields of Cedar Swamp of monoculture grasslands. The hopeful result is that the fire will provide the opportunity for early successional plants will diversify the landscape.
Eric Ludwig, a University of Delaware alum and our guide for the day, informs us that the main species in the fields they target is indiangrass (Sorghastrum nutans). “Indiangrass is structurally very good, but is of very little food value”, Ludwig says. Much of DNREC’s job is to manage the landscape for wildlife populations. In order for quail to thrive, he explains, they require 50% bare ground. When the fields of indiangrass are left unmanaged, they become thick and nearly impenetrable. Our guides explain that, often, prescribed burns are not a sufficient solution. The team has resorted to plowing the fields in some instances, and even lyming the soils. In some circumstances, they even plant a mixture of native plants. “Expense plays a major role in what we’re planting. Right now, we’re planting a native mix: a lot of black-eyed susans, brown-eyed susans, milkweed.” Their goal is to eliminate cool-season grasses. Warm-season grasses, they tell us, do not grow in such a thick mat. They allow for more wildlife habitat.
The burning of the fields does not kill the plants; it simply burns off the tops. Surprisingly, it does not even necessarily kill the animals dwelling in the field. As we stood along the edge of the field at the beginning of the burn, a cottontail burst out of the crackling plants and darted toward us. Seeing the wall of students, the rabbit scurried in a zigzagged pattern and finally paused at the edge of the buffer zone, safe from the flames. The buffer zone is an area just beyond the field that prevents the flames from traveling. More and more cottontails begin to flee the fire. Our guides explain that in many cases, the animals can just hunker down where they are and the fire will pass right over them. It is a quick-burning fire, not quite intense enough to kill anything. They explain that they have found box turtles in the fields that have withdrawn into their shells during the fire, and emerge as soon as the team picks them up. Deer, they tell us, actually run toward the flames. They instinctively know that when a fire is spreading, it is likely safer on the other side.
The fire gradually drew closer to where we were standing. The team made a large circle around the field, lighting the grass as they went. What began as a small sizzling fire a few feet from us soon grew to a large blazing fire on the far end of the field. It circled back around until it was a roaring orange wall in front of us, causing us to clutch our cheeks to protect them from the scorching heat. Though they towered above us, the flames did not cross the approximately 5-foot buffer zone of grass encircling the field. The flames curled back in toward the center of the field, and suddenly were gone. As soon as they reached the center with nothing left to burn, they self-extinguished, leaving us all in awe.