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Rochester/Paleozoic Plateau Upland

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About the Rochester/Paleozoic Plateau Upland

The Rochester/Paleozoic Plateau is an irregularly-shaped region in the western part of the Driftless Area, located in Minnesota and Iowa. This region can be seen as the flatter upland portions of the Driftless Area. It consists of two separate pieces, a northern part that borders glaciated areas to the west, and a southern portion completely surrounded by the driftless area.

The topography here is mostly gently rolling, and it tends to transition gradually from flatter in the areas where it borders glaciated areas to the west, in the north of this region, to slightly hillier as it approaches the steeper, dissected areas of the Blufflands and Coulees of the driftless area. The bedrock here is mostly limestone and dolomite, covered in most places in loess; the loess cap is thickest as one approaches the more dissected regions to the east. Soils here are mostly formed on loess, and the variation in soils here is largely to due the differing histories of the site's vegetation cover: whether the soil formed under prairie or forest. Forest soils (Udalfs) are more common in the northernmost parts of the region, whereas prairie-derived soils (Udolls) become more common to the south.

This region was originally covered with a mosaic of prairie, forest, and transitional savanna. Ridgetops and drier upper slopes supported tallgrass prairie and oak savanna. Brush prairie, a plant community with abundant growth of small shrubs, relatively uncommon in this part of the continent, was found on more mesic sites. Moister slopes supported oak forest. Areas of tallgrass prairie tended to be relatively narrow, but extended unbroken over long distances.

This area has been extensively cleared for agriculture. Nowadays, most of this area is utilized for cropland, mainly corn and soybeans, with slightly smaller amounts of pastureland and hay production. A small portion of land is left as wild forest, mostly the steeper slopes. Very little prairie remains, as the prairie was mostly found on flatter land that is preferred for agriculture. This region contains the city and metro area of Rochester, MN; this metro area is sprawling and has extensive low-density suburban development around its margins, and even the urban center covers a large area relative to its population. There are no other cities of any appreciable size, but there are numerous small towns throughout. There is little protected land, public or otherwise, throughout this region.

The northern section of this region is bordered to the east by the Blufflands and Coulees of the Driftless area, which are at a lower elevation and have much more rugged, heavily-dissected terrain, and more forest cover; the southern section of this region is completely surrounded by the Blufflands and Coulees. The northern part of this region is also bordered to the west by the Eastern Iowa and Minnesota Drift Plains, a flat region that was glaciated. This border is subtle and in most places not marked by any visible topographic features.