Kettle Moraine Oak Opening State Natural Area

Kettle Moraine Oak Opening lies in the heart of the jumbled and rugged landscape of the interlobate moraine, an area of glacially-formed kettle holes, kames (conical mounds), and gravelly hills and ridges. The area is a mixture of oak opening and oak woodland dominated by open-grown bur and black oaks. Small dry prairie openings occur on gravel knobs and steep south and west-facing ridges. Bald Bluff, the largest and most diverse of these, contains short grasses such as little blue-stem, side-oats grama, and prairie drop-seed.

Forbs include pasqueflower, silky aster, grooved yellow flax, and rough blazing star. It also has historical significance: it was visited by Abraham Lincoln when he was in the U.S. Army and it is thought to be a Native American signal hill. The best area of oak opening lies southeast of Blue Spring Lake. It features a big blue stem, Indian grass, purple prairie clover, white camass, lead plant, and Illinois tick trefoil. Intensive management, including prescribed fire and woody species removal, is being used to restore degraded portions and link high-quality areas. Kettle Moraine Oak Opening is owned by the DNR and was designated a State Natural Area in 1991.