Root River, South Fork Professional Review and Guide
"Limestone springs, consistent stocking, and a little help from Mother Nature make the upper Root a premier stream. Southeastern Minnesota may be the least well-known fly fishing mecca in the United States. During the four major glacial epochs, the vast sheets of continental ice that spread southward from Canada seemed to run out of gas as they approached a topographic highland where Iowa, Minnesota and Wisconsin now come together. The Mississippi River flows through the center of the region, creating bluffs of 600 feet that rise from the narrow floodplain to the flat prairie above. Meltwater from the glaciers streamed through existing creek valleys, deepening and steepening them until they reached the level of the river.
Where gradient was steepest, they ate away the land, drawing the heads of the valleys back away from the river for scores of miles. In addition, much of the prairie is underlain by horizontal beds of limestone. Waters from rain and snow dissolve their way through the soluble rock, and issue forth as springs when they encounter impervious beds. Geology and hydrology created the tableau for this marvelous fishery. Species: Brown, rainbow, brook. Angling methods: spin, and fly-fishing."