But the weight of development, a vastly expanded human population and increased demands on the resource are taking their toll. Forest cover has eroded by 10 million acres since Illinois became a state in the early 1800s. What remains is vital to the maintenance of diverse wildlife and plant populations. Though these surviving forests occupy only 12 percent of the state, they contain 75 percent of its wildlife habitat and 61 percent of its native flora. They also are critical to the forest product industry here and to the protection of the state's soil, water resources, air quality and recreational opportunities.
Fragmentation is a product of development, the conversion of forested acreage to non-forest uses.
Examples might include the total destruction of a portion of a forest for agricultural use, construction of a shopping mall or development of a residential subdivision. Or it might involve the establishment of corridors such as interstate highways or other roads through a large forest. Since 1820, Illinois' forested area has plummeted from nearly 14 million acres to the present resource of about 4.3 million acres. The severe fragmentation of that remnant is well documented in current U.S. Geological Survey records. Answers to forest fragmentation may be contained in the relatively new Federal Forest Legacy Program in which the Department of Conservation hopes to participate beginning this year.