Illinois State Museum

photograph of a controlled prairie burn
A controlled prairie burn destroys the encroachment of shrubs and trees.

check Central Prairie - Check the Clues - Maintaining the Prairie

Prairies need fire. Scientists and conservationists are trying to preserve and restore paririe ecosystems in the state. They intentionally set fire to grasslands to burn off dead plant material. Fire adds nutrients to the soil. It also kills woody species, preventing them from invading the prairie.

Which of the following statements is true when there is no fire maintenance of the prairie?

A. The forest and the prairie will both become healthier.
B. The prairie will replace the forest.
C. The forest will begin to move into the prairie.


The correct answer is C. Without fire, trees and shrubs will move into the prairie. It will become smaller and smaller and gradually disappear. Sugar maples will become more common in the forest.