Nerstrand-Big Woods State Park is a state park of Minnesota, USA, northeast of Faribault near the small town of Nerstrand. The park derives its name from the Big Woods, a large, contiguous forested area covering much of central Minnesota prior to the arrival of European settlers. The park and its forest were an outlying 'woods' typical and similar to the Big Woods proper, which were historically found on the more recent glacier deposits located west of the Cannon River 10mi to the west. Aside from a small waterfall, the outstanding natural feature of the park is the forest itself.Natural historyThe Platteville Limestone formation, deposited almost 500 million years ago during the Ordovician Period, forms the bedrock of the park. The limestone is exposed only in a few places along Prairie Creek, most notably at Hidden Falls. The rest of the park is covered in glacial drift up to 150ft deep. A later glaciation passed 10mi to the west, from which meltwater flowed and enlarged the valley of Prairie Creek.This area was once covered in spruce forest, but as the climate warmed after the end of the last ice age, oak stands and prairie became dominant. 400 to 500 years ago the climate cooled slightly, promoting the growth of the Big Woods.In the spring native wildflowers bloom in abundance. A remnant population of the dwarf trout lily, an endangered plant endemic to this area, is present in the park.
