Minnesota: Mississippi River
It’s easy to take the Midwest for ugly, because a casual look around can reveal so little. The horizon is flat and nearly featureless. Driving can seem like an exercise in futility, with the corn and soybean fields, rolling hills and plains, grain elevators and barns blurring together. The mixture of extreme fertility and blunt continental weather is somewhere between hospitable and forbidding. But get to the edge of a major river and things start to come together.
In Minnesota, south of the Twin Cities, the Mississippi flows through a deep channel hundreds of feet below the surrounding plains. Steep slopes capped with limestone bluffs flank the river’s broad floodplain for hundreds of miles. Tributary streams cut through the limestone with networks of steep-sided gullies, or dramatic waterfalls.
The Mississippi’s floodplain is about three miles wide, scooped out on such a grand scale by glacial meltwater. Today the valley is punctuated by deltas from various tributaries, that back up the river into long lakes the full width of the floodplain above them. In between the lakes, the river flows among swampy islands.
From a vantage point like Frontenac State Park, at the top of the bluffs, one can look out over the wide water at the limestone outcroppings stretching out in a row all the way to both horizons, and feel that one is observing nature on a continental scale.
The plain of the Midwest, in this area at least, comes to seem like a plateau. While the top of the plateau may tend to prairie, the steep sides above the water are clothed in lush hardwood forest, dominated by sugar maples (observed in Frontenac State Park). Towns along the river have very hilly terrain, and in some cases dramatic rock formations.
Minneapolis is located where the Mississippi drops into its deep channel, from the north, as it flows down Saint Anthony Falls and a few other rapids. Downstream, the bluffs rise gradually to about 600 feet near Winona, where the surrounding plateau is highest, in the “driftless area” unaffected by glaciers.
In Minnesota, south of the Twin Cities, the Mississippi flows through a deep channel hundreds of feet below the surrounding plains. Steep slopes capped with limestone bluffs flank the river’s broad floodplain for hundreds of miles. Tributary streams cut through the limestone with networks of steep-sided gullies, or dramatic waterfalls.
The Mississippi’s floodplain is about three miles wide, scooped out on such a grand scale by glacial meltwater. Today the valley is punctuated by deltas from various tributaries, that back up the river into long lakes the full width of the floodplain above them. In between the lakes, the river flows among swampy islands.
From a vantage point like Frontenac State Park, at the top of the bluffs, one can look out over the wide water at the limestone outcroppings stretching out in a row all the way to both horizons, and feel that one is observing nature on a continental scale.
The plain of the Midwest, in this area at least, comes to seem like a plateau. While the top of the plateau may tend to prairie, the steep sides above the water are clothed in lush hardwood forest, dominated by sugar maples (observed in Frontenac State Park). Towns along the river have very hilly terrain, and in some cases dramatic rock formations.
Minneapolis is located where the Mississippi drops into its deep channel, from the north, as it flows down Saint Anthony Falls and a few other rapids. Downstream, the bluffs rise gradually to about 600 feet near Winona, where the surrounding plateau is highest, in the “driftless area” unaffected by glaciers.
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