At Grainger Woods, mesic oak woodlands, wetlands, meadows and prairies harbor several state-listed threatened and endangered species including a sedge not seen in the Chicago region since 1955.
The site’s rare northern flatwoods contain mainly swamp white oaks, black ash, musclewood and hop hornbeam. Seasonally flooded woods, flatwoods are wet in the spring and fall and dry during summer. The site also features a large formerly-grazed pasture that is slowly returning to its original prairie state as evident by emerging native plants including prairie dock, golden ragwort, blue-eyed grass, large yellow fox sedge, crested oval sedge, wild strawberry and other plant species.
While there are no trails here, the two natural communities found on the site include a wet-mesic prairie and a high-quality sedge meadow that contain more that 165 native plant species. Healthy, native plants are now thriving in pastures where horses once grazed.
Townline Stables operates a boarding stable at the northwest corner of the preserve.