AY-215

(SOIL CLASSIFICATION)

Cooperative Extension Service

Purdue University

West Lafayette, IN 47907



Types and Uses of Soils Information in Indiana



G. C. Steinhardt, D. P. Franzmeier, and J. E. Yahner
Department of Agronomy, Purdue University




People make decisions every day about soil and land use. Wrong decisions can lead to problems, not just for individuals but for whole communities as well. In fact, many of the problems facing Indiana communities today, such as flooding, septic tank failure, and erosion, can be traced to improper use of soils.

Information contained in soil maps and soil survey reports can be valuable in guiding decisions that will avoid land-use mistakes. The purpose of this publication is to review briefly the types of soil information available to Hoosiers, how it's gathered, how it can be used, and where it can be obtained.

THE VALUE OF SOILS INFORMATION

Soils information is usually presented as a map showing the distribution of the soils present in a particular area. The properties considered in classifying those soils include: soil texture, organic matter, natural drainage, permeability, water holding capacity, position in the landscape, slope, and degree of erosion. Soils with similar properties are then grouped into mapping units. From these mapping units, soil scientists can predict the response of specific soils to various uses and management systems. Following are some examples of areas where soils information can be helpful.

Agriculture. Soil maps and soil survey reports can help farmers to better manage their land. They are especially useful when beginning a farming operation on a new site. Soil maps can also be the basis for assessing cropland drainage needs, selecting a tillage system or soil fertility program, evaluating suitability for irrigation, adopting erosion control, or utilizing other cultural practices.

Forestry and Recreation. Soil survey information can be the basis for predicting the best tree species to grow at a given site as well as the basis for a good management program. It can also identify those areas where recreation would be the best land use, based on soil properties.

Residential Planning. Soil maps can be used to evaluate homesites for potential problems of flooding, seepage, foundation cracking, and septic system failure. Land developers should also consult soil maps in their planning to avoid soil problems during construction and after housing development is completed.

Community Planning. Soil surveys can assist local government officials and planners in realistically relating community goals to the natural resources available for development, while assuring preservation of an area's most productive farmlands.

HOW SOILS INFORMATION IS GATHERED

Indiana is part of the National Cooperative Soil Survey Program. Within our state, this is a cooperative effort between the U.S. Department of Agriculture's Soil Conservation Service, the Agricultural Experiment Station at Purdue University, and the Indiana Department of Natural Resources.

Indiana has completed a detailed soil survey for each of the 92 Indiana counties. Data for detailed county surveys were collected by soil scientists who walked over the land and examined the soil profile with an auger to a depth of about 5 feet. From their profile examinations and observations of the landscape, the scientists identified each soil and marked its location on an aerial photograph. When all soils in a county were mapped and their properties described, the map descriptions and supplementary information were assembled into a published soil survey.

Based on these detailed maps and research studies, more general maps have also been made to cover larger areas.

TYPES OF SOIL MAPS AVAILABLE

Indiana citizens have access to several types of maps developed to fit almost every need. Following is a discussion of each type of map and its appropriate use.

County Detailed Soil Surveys

These are the most detailed collections of soils data. They are printed at a scale of either 4 or 3.2 inches per mile and are available for most counties. They are appropriate for planning specific uses of soils. Included with the multi-page map is a description of the soils, a discussion of the limitations of the soils for various uses, and data from routine soil analysis and engineering tests.

Table 1 shows the completion date of detailed soil surveys in Indiana by county. Those counties that do not have a published survey have a scheduled date for publication. Completed field soil maps are available in the Soil and Water Conservation District office for those counties that do not have a published survey.

Table 1. Status of Indiana County Detailed Soil Surveys (1/87).



                Date        Scale                      Date         Scale
County        published*  (in./mi.)       County       published*   (in./mi.)
----------------------------------------------------------------------------------------
Adams            1986              4           Lawrence          1985             4
Allen            1969              4           Madison           1967             4
Bartholomew      1976              4           Marion            1978             4
Benton           1989              4           Marshall          1980             4
Blackford        1986              4           Martin            1988             4
Boone            1975              4           Miami             1979             3.2
Brown          	 1990              4           Monroe            1981             4
Carroll          1991              4           Montgomery        1990             4
Cass             1981              4           Morgan            1981             4
Clark            1974              4           Newton            1997             4
Clay             1982              4           Noble             1977             4
Clinton          1980              3.2         Ohio              1981             4
Crawford         1975              3.2         Orange            1984             4
Daviess          1974              3.2         Owen              1964             4
Dearborn         1981              4           Parke             1967            3.2
Decatur          1983              4           Perry             1969             4
DeKalb           1982              4           Pike              1987             4
Delaware         1972              4           Porter            1981             4
Dubois           1980              4           Posey             1979             4
Elkhart          1974              3.2         Pulaski           1968             4
Fayette          1960              4           Putnam            1981             4
Floyd            1974              4           Randolph          1987             4
Fountain         1966              4           Ripley            1985             4
Franklin         1990              4           Rush              1986             4
Fulton           1987              4           St. Joseph        1977             4
Gibson           1989              4           Scott             1962            3.2
Grant            1989              4           Shelby            1974             4
Greene           1989              4           Spencer           1973             4
Hamilton         1978              4           Starke            1982             4
Hancock          1978              4           Steuben           1981             3.2
Harrison         1975              3.2         Sullivan          1971             4
Hendricks        1974              4           Switzerland       1987             4
Henry            1987              4           Tippecanoe        1997             4
Howard           1971              3.2         Tipton            1989             4
Huntington       1982              4           Union             1960             4
Jackson          1989              4           Vanderburgh       1976             4
Jasper           1989              4           Vermillion        1978             3.2
Jay              1986              4           Vigo              1974             3.2
Jefferson        1985              4           Wabash            1983             4
Jennings         1976              4           Warren            1990             4
Johnson          1979              4           Warrick           1979             4
Knox             1981              4           Washington        1988             4
Kosciusko        1989              3.2         Wayne             1987             4
LaGrange         1980              3.2         Wells             (90)             4
Lake             1972              4           White             1982             3.2
LaPorte          1982              4           Whitley           1990             4
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*Dates in parentheses are estimated publication dates for forthcoming
surveys in which field work has been completed. If two numbers are in
parentheses, an older published survey is currently available. For
example, a 1958 survey of Carroll county is now available, and a new
one is scheduled to be published in 1990. 

Computer Storage of Soil Maps and Interpretation

The Fast Agricultural Communications Terminal System (FACTS) Soil Survey Interpretation System (SMIS) is a program for computer storage and interpretation of detailed county soil surveys. Its purpose is the development and rapid recall of a county-wide soils data base. In addition to soil maps, property ownership maps are also entered to allow location and interpretation of individual land parcels. Further program development will include the addition of land use as a third map input. The program also contains space for the future addition of drainage ditch watersheds.

In addition to storing maps, the program also contains a variety of interpretations for each soil map unit. Interpretations can include crop yield potentials, tillage management groups, septic system ratings, drainage groups, and other useful values associated with soil map units. The program can provide not only printouts of the soil map but also individual interpretations. The program has been developed for use on the county FACTS computer terminals. Thus its use does not require digitizing capability in the FACTS computer. The data base is constructed in the county, and output is available at local Purdue Cooperative Extension Service offices. At present the program is being used to develop data bases in several counties. More will be starting in the future. The completed data base has many uses suited to a wide variety of groups and individuals in the county.

State Soil Map

This soil map, AY-209, "Map of the Soil Associations of Indiana," is about the size of the state highway map, and it groups soils over landscape units called state soil associations. The state soil map is useful to soil specialists and planners in finding regional properties of Indiana soils. It has served as a guide to determine which regions of the state have the most prime agricultural land and which regions are best suited to conservation tillage and also to predict the best regions for irrigation. It can be useful to the interested traveler who wants to get a view of the soil resources of Indiana.

Printed on the state soil map is a much smaller map showing the "state soil regions," which reflects the geologic material from which the soils were formed. It is most useful to teachers and geologists to illustrate geology and soil-forming processes.

OTHER PUBLICATIONS ABOUT INDIANA SOILS

Indiana Soils and Landscapes (AY-250)

This publication contains a more detailed explanation of the formation and distribution of Indiana soils on a statewide basis. The entire state is divided into six soil resource areas. Each resource area is distinguished from the others by differences in the factors of soil formation. The factors of soil formation include: parent material from which the soil forms, climate, vegetation, topography, and time.

For each of the soil resource areas the surface geology is discussed, as is the distribution of soils on the landscapes of the area. The landscapes are discussed as associations, and the locations of the soils on these landscapes are shown in block diagrams. Generalized land use data are given for each association. Accompanying the publication is a series of soil association maps. These maps are joined together to cover the entire soil resource area.

Key to Soils of Indiana (AY-249)

This publication contains a key showing the relationship of soils to each other and to some of their environmental factors, such as parent material, native vegetation, and topography as expressed in natural drainage. The key index lists all soil series correlated since 1955. Most of these series are considered to be active in Indiana and appear in the body of the key. Some of the series names in the older surveys are no longer being used in the state. For each of these, the name of an equivalent active series is listed in parentheses in the index.

In the body of the key, soils are grouped according to the soil region in which they mainly occur. Some soil regions are subdivided according to major landforms, such as organic soils and mineral soils, and floodplains and terraces.

Indiana's Soil Series and Their Properties (AY-212)

This publication alphabetically lists soil series that were used on county soil surveys. Properties included for each series are those needed to understand use, management, and potential value for agriculture.

First, features are arranged to indicate the general nature of the soil, its drainage class, and usual range of surface slopes. Then selected surface soil, subsoil, and substratum features needed to understand the soil series to a depth of about 60 inches are given. Water movement, available water capacity, erosion potential, and depth favorable to rooting are indicated as a means of explaining the potential productivity of the soils for corn, soybeans, wheat, and hay. Potential increases over today's top production levels and decreases due to severe erosion are also included.

HOW TO OBTAIN SOIL MAPS AND OTHER PUBLICATIONS

Copies of detailed county soil surveys (listed in Table 1) are available from county Soil and Water Conservation District offices. The computer stored county soil map and interpretations, if available, are located at Purdue Cooperative Extension Service offices.

Single copies of AY-209, "Map of the Soil Associations of Indiana," are available at a cost of $.50 each; AY-249, "Key to Soils of Indiana" has a cost of $1.00; these are available from county CES offices or from the Media Distribution Center, 301 South 2nd Street, Lafayette, IN, 47905-1092. The following publications are available only through the Media Distribution Center at the prices specified: AY-212, "Indiana's Soil Series and Their Properties" (1.00); and AY-250, "Indiana Soils and Landscapes" ($9.50).


Rev 5/96

Cooperative Extension Work in Agriculture and Home Economics, State of Indiana, Purdue University and U.S. Department of Agriculture Cooperating. H.A. Wadsworth, Director, West Lafayette, IN. Issued in furtherance of the Acts of May 8 and June 30, 1914. It is the policy of the Cooperative Extension Service of Purdue University that all persons shall have equal opportunity and access to our programs and facilities.