Blue Mounds State Park and Vicinity Professional Review and Guide
"Just when the prairie looks like it has nothing more to offer, something new captures the horizon. So it is with Prairie Coteau, or as the French named it, “Coteau des Prairies” (“Highland of the Prairies”), an approximately 40-milewide area rising 500-800 feet above the flatland, running southeast to northwest through southwestern Minnesota and into South Dakota. Underlain with Sioux Quartzite, the coteau primarily resisted the glacial forces that shaved flat surrounding areas, and its surface is marked by lakes and wetlands.
On the coteau’s east side, deep wooded valleys, historically protected from prairie fires, provided homesteaders with their westernmost source of hardwoods. On its west side, the “West” truly begins, dominated by vast grasslands and even isolated populations of prickly pear cactus. Outside the coteau, other Sioux Quartzite sites swell up on the flat prairie, and they are well known today. Blue Mounds State Park marks a rise where grasslands appear blue from a distance under the heat of a summer sky. Key birds: Swainson’s Hawk, Upland Sandpiper, Willow Flycatcher, Sedge Wren, Orchard Oriole, Blue Grosbeak, Dickcissel, Grasshopper Sparrow."