This state-dedicated nature preserve features a complex of sand prairie, oak savanna, and wetlands. More than 400 species of plants have been identified, many of them state-listed. Prickly pear cactus produces its showy yellow blossoms in early summer. An outstanding display of prairie wildflowers attracts a variety of butterflies in late summer. Coulter is a good place to find blue racers, hognose snakes, and six-lined racerunner lizards.

The Yellow Birch Fen section of Coulter Preserve comes alive in the early spring. Skunk cabbage emerges from the mud to unfurl its large glossy leaves and showy ferns develop from delicate fiddleheads. Marsh marigold, Canada Mayflower, May apple, wild columbine, wild geranium, starflower, and many other lovely wildflowers follow in short order.