The most recent North America glacier invasion's final gasp scoured a marsh out of Wisconsin limestone. The area would later be called Horicon (pure). This is where the Green Bay lobe of the massive Wisconsin glacier stopped and relinquished the load of boulders that it had relentlessly carried down from the north.
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That deposit became the Niagara escarpment: the point on our continent that separates the waters that flow eastward into Lake Michigan from those that flow into the Mississippi River.
The latter formed a lake here ten thousand years ago. But, fortunately for the wild geese, as silt and sediment built up, the lake transformed into a marsh.
Horicon is the largest freshwater cattail marsh in the United States, covering over 32,000 acres. It's a critical rest stop for thousands of migrating ducks and Canada geese, recognized as a Wetland of International Importance. It is also a gem among the points of interest that lie on Wisconsin's Ice Age Trail.
A fall visit to Horicon provides a front row seat to the phenomenon of migration.
The sky is filled with "V" formations. The geese's honking is ever so much louder than the uninitiated would imagine-- filling the marsh, ringing out across the wetlands. As wetlands disappear across the continent, and up to 90% or more of it has, the geese congregate at this queen of the sites that remain.
Horicon is the source of the Rock River, where three small branches conjoin to form the river that empties into the Mississippi only a mile or two from my Iowa home. We followed the route of the river on our journey to Horicon, tracing it from end to beginning.
There are both a federal and a state-governed area of the marsh, and it's large enough to support both agencies with room to spare. We limited our visit to the federal recreational areas and visitor center (pictured above).
|Mounted goose appears to watch as visitor signs the register at the Visitors Center at Horicon Marsh.|