The Soil Survey Manual, USDA Handbook No. 18, provides the major principles and practices needed for making and using soil surveys and for assembling and using related data. The term "soil survey" is used here to encompass the process of mapping, describing, classifying, and interpreting natural three-dimensional bodies of soil on the landscape. This work is performed by the National Cooperative Soil Survey in the United States and by other similar organizations worldwide. The Manual provides guidance, methodology, and terminology for conducting a soil survey but does not necessarily convey policies and protocols required to administer soil survey operations. The soil bodies contain a sequence of identifiable horizons and layers that occur in repeating patterns in the landscape as a result of the factors of soil formation as described by Dokuchaev (1883) and Jenny (1941).

This book, specially prepared for soil scientistsand engineers, offers comprehensivecoverage of basic soil concepts, systematics,mapping and examination procedures forsoils. The Manual is universally useful andis the primary reference on principles andtechnical detail for local, State and Federalcontributions to authorized soil surveys.Soil scientists concerned with soil surveysin other countries have used it as well.Teachers have used it both as a text and as areference for students.

Undisturbed marshes, swamps, and overflow lands have many inherent values and a variety of uses. This report is confined to the use of these natural wetlands by wildlife. Millions of Americans rely on wild animals to furnish them with healthful outdoor recreation. Other values of wetlands include the storage of ground water, the retention of surface water for farm uses, the stabilization of runoff, the reduction or prevention of erosion, the production of timber, the creation of firebreaks, the provision of an outdoor laboratory for students and scientists, and the production of cash crops such as minnows (for bait), marsh hay, wildrice, blueberries, cranberries, and peat moss. Some wetlands provide good fishing. This report points out relative values of different types of wetlands to wild game in general and to waterfowl in particular. It locates and describes areas that should be protected and improved to meet the needs of a stable or increasing waterfowl population. The information is presented with the fervent hope that it will assist and stimulate the establishment of more comprehensive land-use programs and policies. The inventory was financed largely by funds derived from the sale of Federal Duck Stamps. The wetlands data on which this report is based were gathered by the U.S. Fish and Wildlife Service with the cooperation of various State fish and game agencies. Much of the assessment of waterfowl values was made by State biologists for their respective States.

Written from the point of view of the earth scientist, this book acts as an introduction to terrain evaluation. The emphasis throughout is on the physical rather than the economic, social or legal aspects of the subject, and topics covered include remote sensing and data processing technologies.