ALTO PASS, Ill. (AP) — Forestry workers have started selectively removing trees from the Trail of Tears State Forest in southern Illinois in hopes of restoring native plants and oak trees.

The number of oaks has declined by half since 1980, depriving wildlife of food. Oaks need a lot of sunlight and are declining because growth in American beech and maple trees has made the canopy denser and shadier.

The 5,000-acre forest is home to around two dozen species of concern for conservationists, including the state-threatened timber rattlesnake and rice rat, and, possibly, the federally endangered Indiana bat.

The Illinois Department of Natural Resources says selective tree removal began Tuesday on 142 acres in an area of the forest set aside for attempts aimed at restoring its diversity of plant life and wildlife.