Saint John's Marsh

St. John's Wet Prairie Natural Area is part of a highly significant cluster of lakeplain prairies within the St. Clair River delta. Lakeplain prairies are relatively flat, occurring on sand ridges overlaying clay. High water tables fluctuate seasonally and, over the years, with the rise and fall of the Great Lakes. Fires were also important for maintaining lakeplain prairies. Close to 160 different kinds of plants, including many showy prairie wildflowers such as blazing star and tall sun flower and grasses such as big blue stem and Indian grass, grow in St. John's Wet Prairie Natural Area.