The 9th Natural Division on the map is the Lower Mississippi River Bottomlands Division stretches along the Mississippi River, from Madison County south to the northern part of Alexander County. (map)
This division includes the Mississippi River and its floodplain from Alton to the Thebes Gorge. The Mississippi River is muddy here due to the silt load brought in by the Missouri River. The soils have developed from this alluvium and are either finely textured and well-drained with areas of sand, or clayey with poor drainage. The division is divided into two sections—the Northern, which originally contained prairies, marshes, and forest, and the Southern, which was densely forested. The Northern Section contains the American Bottoms, a montage of swales, backwater lakes, ridges, and river terraces. When Charles Dickens visited the area in 1842 all he could hear was the loud chirping of frogs and all he could see on the “unwholesome, steaming earth” was mud, mire, brake (overgrown marshland) and brush. Horseshoe Lake, which is a U-shaped ox-bow, is now a state park. The Southern Section’s forests have not only pin, overcup, and cherrybark oaks, but also species associated with bottomland swamps. Look for pumpkin ash, swamp cottonwood, and bald cypress in La Rue Swamp and listen for the calls of green treefrogs.