Importance:
The natural area encompasses a portion of a complex of forested
dunes and swales. The dunes formed as lake levels receded, beginning
approximately 12,000 years ago, depositing a series of low sandy
beach ridges, ranging from 0.5 to 3 meters high. Since then, the
ridges have become forested and the wet swales that developed
between them are now either forested or open wetlands. In Michigan,
there are fewer than 50 remaining examples of forested wet swale
communities of this quality.
This area supports one of the largest
known populations in the world of the federal and state-threatened
dwarf lake iris, Michigan’s state wildflower. Thousands of iris
shoots, and several other plant species of special concern grow in
the area.
Thompson's Harbor Natural Area was
legally dedicated in 1979. The estate of Genevieve Gillette, a
Michigan resident vital to establishing the Wilderness and Natural
Areas Program, aided state acquisition of this property. |