Knox College's annual prairie burn brought together students and faculty as they set a controlled fire to the prairie land at Green Oaks Biological Field Station. The 12 Students, along with Associate Professor of  Art Tony Gant, assisted Professor of Biology Stuart Allison in setting the fires. 

The annual burns aim to protect prairie grasses from intrusions of woodland scrub and competition with exotic species that have been introduced to Illinois from other regions or countries.

Allison commented that in addition to ecological benefits of restoring and enhancing native Midwestern prairies, there's an important cultural dimension to the controlled burns.

"One of the reasons we have prairies and not just trees in Illinois, at the time of European settlement, is because Native Americans had been burning continuously for four to five thousand years," said Allison, speaking at this year's burn in late March.

"Prairie grasses and trees are competitors," he explained, as a dozen Knox students set fire to the sections of restored prairie at Green Oaks.

"In Illinois, there's enough moisture that trees would eventually encroach many of the prairies and shade them out. Further west, it's so dry that trees can't take over. But if you're going to maintain prairie in Illinois, you're definitely going to have burning." 

According to Allison, who holds the Watson Bartlett Professorship in biology and conservation, controlled burns simulate the natural fires that originally resulted in the Midwestern tallgrass prairies. Much of the Illinois prairie has now been erased by settlement, agriculture, and development.

"We're maintaining that tradition of burning prairies, keeping them open. It's both an ecological and a cultural activity," Allison said.

Most burns at Green Oaks are held on a three-year rotation, believed by many researchers to be the most effective at suppressing invasive plant species. This year, the burn area encompassed Woodcock Field and Shepard Prairie, a total of about eight acres. 

Shepard Prairie is named in honor of Paul Shepard, a biology professor at Knox who was instrumental in the inauguration of prairie restoration at Green Oaks in the 1950s. The area was familiar territory to Rafael Cho, a senior on the burn crew who studies environmental studies and biology.

"Over the summer of 2018, I did research on prairie soils, working right in this prairie that we're burning today," Cho said. "I took soil samples, comparing characteristics such as the depth of the
top soil, how much organic matter was in it."

"Here in the burn field, some roots get burned and some don't. The prairie plants have deeper roots, they're more fire-resilient. The non-native plants have shallower roots, closer to the surface," he added.

The sections of restored prairie burned this year represent a small fraction of the total area of Green Oaks. With approximately 700 acres of prairie, forests, and aquatic habitats, the site is the subject of numerous research projects.

Students who participated in Prairie Burn 2019 were:

Luba Liubvina
Rafael Cho
Katerina Sasieta
Maggie Decker
Monica Martinez
Erika Riley
Jessica Totten
Jankhi Bhalodi
Grace LaDuca
Montse Cancino Aguilar
Kendra Bates
Allie Glinski