Cook County Woods Need Work

Many people know that the 68,000 acres of lands held in the Forest Preserve District of Cook County contain rare ecosystems and habitat for increasingly rare plants and animals. But to what extent are these lands fulfilling their potential as healthy ecosystems? A new study by Deborah Antlitz, a staff ecologist with the district, provides further evidence that the picture isn't pretty. But it also gives specific recommendations on how to bequeath a healthy preserve system to future generations.

Using Global Positioning System computer software, the district divided its land holdings into three categories: wooded lands, open lands, and wetlands. Then district staff visited 50 random points within each category to survey the vegetation.

According to the study, of Cook County's 68,000 acres, 55,000 are in a natural or potentially natural condition. Of this, 34,000 acres, or 62 percent, were found to be of poor quality, harboring few to no native plant species. The remaining 21,000 acres contain remnants of natural communities, such as prairies and oak woodlands. Of these 21,000 acres, 16,000 acres are failing to achieve their full potential as healthy ecosystems.

The cause behind this failure is the now familiar list of exotic and native plant species run amok, disturbance of water flows, overabundance of deer, and a wide range of side effects from decades of fire suppression.

To restore these lands, the study recommends an intensive and ongoing program of controlled burns, deer population management, invasive species control, and other measures. Corrective activities cited by the district include the removal of selected excessive shrubs, saplings, pole-sized trees, along with wholesale removal of buckthorn and garlic mustard on some 10,000 acres. Selected invasive native trees should be removed from 6,000 acres, the study said. Hundreds of acres of wetlands need the control of reed canary grass and purple loosestrife and the disabling of old drainage tiles and ditches to bring back ecosystem health. Friends of the Forest Preserves, Sierra Club, Audubon and many other groups have applauded the district's renewed dedication to its mission.

— Douglas Chien