THE ICE STOPPED HERE
Libby Reuter and Joshua Rowan
Mill Creek Natural Area (near Piney Creek)
Randolph County, IL
In an earlier period of climate change, the Pleistocene Epoch (1.6 million to 10,000 years ago), ice covered 85 percent of what is now the state of Illinois. Only the northwestern corner and extreme southern parts of the state, along with Calhoun County and parts of Pike, Jersey, Monroe, and Randolph counties, were not glaciated. As the ice moved southward, the glaciers scraped the surface of the land carrying soil with them. When the climate began to warm, the ice melted, and the seeds the glacier had carried from Wisconsin and northern Illinois were deposited. http://dnr.state.il.us/education/biodiversity/glaciation.htm
This Cairn marks a special place at the edge of the ancient glacier’s reach in Randolph County. Here, the sandstone canyons and gorges create a cool microclimate where club moss, cinnamon fern, and bishop’s cap, not normally found in southern Illinois, have survived for eons.
http://www.voyageurcountry.com/htmls/floweringplants/plants/clubmoss.html – http://www.fcps.edu/islandcreekes/ecology/cinnamon_fern.htm http://www.illinoiswildflowers.info/woodland/plants/bishop_cap.htm
Heartlands Conservancy, (Investing in Southwestern Illinois) and Cifftop, (Protecting our Bluffs in Monroe, Randolph and St. Clair counties) collaborated to purchase and preserve this unique ecological system. Currently, the area is open only for special tours.