Soils of the Central Feed Grains and Livestock Region and Lake State Fruit, Truck Crop, and Dairy Region USA: LRRs M and L

Abstract

Land Resource Regions (LRR) M and L occupy predominantly the northcentral part of USA with the exception of MLRA 101 (LRR L) located on the northeastern part bordering Lake Eire. Both regions have been influenced by several glaciations that occurred between 10,500 and 2,500,000 years ago. The geology is dominated by Devonian/Ordovician rocks, sedimentary and granitic, and to a lesser extent by Cambrian (9 %) and volcanic (8 %) rocks. Soils in the regions have developed mostly on loess, till, and outwash materials deposited after glacier melt. The predominant soils are Mollisols and Alfisols formed on loess followed by Spodosols, Entisols, and Inceptisols formed on outwash rmaterials on stream terraces and valleys. Histosols are limited in extend occurring throughout the region on localized depressions. The region that is also known as the “Bread Basket” of the USA is comprised of soils that are relatively young and among the most fertile in the world. The rolling hills, loess plains, and outwash valleys support a wide variety of crops. Soils are neutral to slightly alkaline for the most part and relatively high in organic matter due to favorite climate conditions and historical predominantly prairie vegetation. Intensive agricultural practices have caused extensive erosion and systematic depletions of fertility and organic matter and continue to remain major concerns for soil resource management and environment issues such as water quality.