The goal of restoration is to reverse – to the extent possible in the midst of a busy metropolis – the unnatural effects of the past two hundred years and to restore the natural conditions that sustained our landscape for the last 10,000 years.
Many plants which were once abundant are now rare or in danger of becoming extinct, and the conditions for their survival tend to get worse over time. Restoration is all about allowing those 1600 species—and the birds, butterflies, amphibians and other animals that depend on them—to thrive. With farmland, cities and suburbs comprising most of the land in Illinois, forest preserves are some of the few places left that can even hope to support them.
Aggressive non-native plants such as European Buckthorn, Garlic Mustard and White Sweet Clover are removed so that native species have a better chance to grow and reproduce. Some of the brush and understory that chokes the woods are removed, letting more sunlight reach the forest floor. Herbicide is carefully dabbed on the surface of stumps to prevent resprouting. Seeds of local native plants are collected from some sites and redistributed to others, returning or increasing the native plant populations in areas where they had been dying out. Restorative fire is returned through the use of periodic controlled burns. For the last forty years, such burns have been conducted in a safe, responsible manner by trained personnel under the supervision of the Forest Preserve District, with proper permits, and notification of local fire and police departments.
The oak forests of northern Illinois have taken centuries to develop, and deserve to be regarded as an irreplaceable landscape legacy distinctly characteristic of our region.
If we are to keep the oak trees which we value, we must begin by understanding that the oaks are integral parts of a system made up of living and nonliving things which have developed over a very long period of time. Certain conditions [are] vital to the life of these oak trees, and we must either preserve these conditions or provide a successfully functioning simulation of these conditions.
From The Care and Management of Native Oaks in Northern Illinois
by George Ware and Virgil K. Howe