a belt about 80 km (50 mi) wide along the Missouri River, thedissected plains are thickly mantled with loess. South of the Missouri River, along the Kansasborder, the Osage Plains are more open and undulating.The third major physiographic region, the Mississippi Alluvial Plain, or Bootheel, consists of theseven southeastern counties. The flat surface slopes slightly southward from the foot of the OzarkEscarpment. Rivers and LakesThe Mississippi and Missouri rivers dominate the state's drainage system. The streams of northernMissouri flow generally southward across the till plain to these rivers. In southern Missouristreams flow away from the crest of the Ozark Highland in all directions. Ozark streams are fedby a complex network of underground drainage systems, and their discharge is relatively stablethroughout the year.Missouri's largest lakes are artificial. The Lake of the Ozarks, formed by damming on the OsageRiver, is one of the world's largest artificial lakes. Groundwater is abundant.Plant and Animal LifeAt the time of white settlement the flatter parts of the Plains region were covered with prairiegrass that reached heights of 2 m (7 ft). The more dissected parts were covered with hardwoodforests. In the Ozarks an oak and hickory woodland prevailed, with short-leaf pine intermixed inthe east. The Mississippi Alluvial Plain had a lowland forest of bald cypress, tupelo, andsweetgum. At present, new-growth commercial forests are gaining importance, and only in theBootheel and the Osage Plains have farms and pastures blocked reforestation. The varied andabundant wildlife of Missouri includes deer, wild turkeys, and bears. ClimateMissouri has a continental climate with hot, humid summers and cold winters. Because it lacksmajor topographical barriers, the state has a gradual climatic differentiation, warming fromnorthwest to southeast. The clash of contrasting air masses in spring and fall may set off violentthunderstorms, some of w...
