It was not a rattlesnake
The Wisconsin DNR contacted me today. This IS NOT a Timber Rattlesnake. I started having my doubts the more I read.
This was a Fox Snake. They can emulate a rattling sound and are often mistaken for Timber Rattlesnakes.
If this was a Timber Rattlesnake, it would have greatly extended the known range, as they are an endangered species when they used to be quite common in the Driftless Area.
Thanks to Richard at the Wisconsin DNR for taking a look at this for us.
The snake was left to enjoy our property, and I appreciate it letting us enjoy the property also.