5.0 - Introduction
This lesson discusses the characteristics of the 12 soil orders defined by the USDA soil classification system, the major factors involved with their formation, and their geographic distribution across the USA and the world.
This lesson was developed by Martha Mamo, Timothy Kettler, and Dennis McCallister at the University of Nebraska-Lincoln; Jim Ippolito Research Soil Scientist, USDA-ARS-NWISRL, Kimberly, Idaho, formerly at Colorado State University ; Ron Reuter at Oregon State University; Christoph Geiss at Trinity College-Connecticut; and William Zanner at the University of Minnesota. Development of this lesson was supported by the National Science Foundation Course, Curriculum, and Laboratory Improvement Program (NSF-CCLI), Award Number DUE-0042603. Any opinions, findings, conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of NSF.