Digital Soil Mapping in Minnesota

This site provides information about a variety of county-level and statewide digital data sets that describe the soils of Minnesota. Status information and links to detailed descriptions of the characteristics and limitations of the data sets are provided. Most of the data is available free online.

Background | County Data | Statewide Data | Published Soil Surveys | Crop Productivity Index Ratings | Contact Info
 


Background

In a 1994 survey of Minnesota GIS users, digital soils data was identified as the number one data need. There was a particular need for detailed data sets based on the printed county soil surveys created by the Natural Resources Conservation Service. To help focus a plan for obtaining these detailed data sets, the Minnesota Governor's Council on Geographic Information published County Soil Surveys: Guidelines for Digitizing (June, 1997). Each county's printed soil survey was placed into one of four categories based on whether the soil classification was modern or outdated and whether or not the survey had been produced using an orthophoto basemap. (See the map on page 7 of the report showing the category for each county.) For more information about the creation and uses of the printed surveys, see a brief history of soil mapping in Minnesota.

The report recommended various digitization options and discussed intermediate digital products that could be used until higher quality data became available. Substantial progress on creating county-level digital data has been made since the report was published.
 


County-level digital data

The data sets described in this section were created from the printed county soil surveys from the Natural Resources Conservation Service. Currently, the areas included in these different data sets cover most of the state; they are all free online.

  • SSURGO:  The Soil Survey Geographic data set (SSURGO) from NRCS is considered the best available digital soils data in Minnesota.
    • Web Soil Survey: View soil maps and reports on the web, without having to download the data. This NRCS site makes SSURGO soil data much more accessible to the general public.
    • Download or order on CD:  Several download options are available; also find links for more information about SSURGO.
    • Minnesota status map from NRCS showing the progress of SSURGO data sets currently completed, planned or in production

       

  • Soil Survey Information System (SSIS):  Soils data for about 40 Minnesota counties was collected using the Soil Survey Information System. SSIS is a non-GIS computer program created by the University of Minnesota Department of Soil, Water and Climate in the mid-to-late 1970s. It was used to collect and display soil information from the NRCS county soil surveys on a section-by-section basis. Many of the SSIS files have been converted to GIS formats and put together into public land survey township tiles.
    All SSIS data has been superseded by SSURGO data from NRCS. SSIS data will remain online, however, for historical completeness.

Statewide digital data

The three statewide data sets are less detailed than the county data sets; however, they provide information for areas not yet covered by county-level data sets and are suitable for statewide or regional analysis.
  • U.S. General Soil Map (STATSGO2): The State Soil Geographic database, created by the Natural Resources Conservation Service, shows the boundaries of soil associations at a scale of 1:250,000. Soil associations are more general than the soil series mapped in NRCS's county soil surveys. The data and full documentation are free online from NRCS.
  • Minnesota Soil Atlas: This 1:250,000-scale data set shows soil landscape units created using combinations of four characteristics:  sub-surface soil texture, surface soil texture, drainage, and surface color. It was created from the preliminary Minnesota Soil Atlas sheets developed by the Department of Soil Science, University of Minnesota, in cooperation with NRCS. It is available free online.
  • Cummins and Grigal: This 1:1,000,000-scale data set, available on the Minnesota.data CD, Volume 1, contains polygons based on areas of common soil and landform characteristics, and is useful for regional analysis. See the map's companion document, Legend to Map:  Soils and Land Surfaces of Minnesota 1980 (PDF, 3542K), J.F. Cummins and D.F. Grigal, Department of Soil, Water and Climate, University of Minnesota Agricultural Experiment Station.
     

Published county soil surveys

The published county soil survey books from NRCS are divided into three parts:  Part 1 provides a general description of a county's soils; Part 2 contains detailed soil descriptions and information on the use and management of the soils; Part 3 contains a general map of soil associations and many detailed maps of soil series overlaid on an air photo background. Note that NRCS is no longer publishing these books on paper; many books are available as PDF files that can be downloaded.

  • Printed copies: List of published surveys, publication dates and contact information for Minnesota NRCS.
  • Online: Soil surveys for about half of Minnesota's counties are online in PDF format from NRCS.
  • Online tables: For each Minnesota county, Section II of NRCS's electronic Field Office Technical Guide (eFOTG) provides access to tables of soil properties.
  • National Soil Survey Handbook: Detailed explanation of NRCS's soil update procedures. Use the Contents to navigate to Section 608.08.
  • History and uses of Minnesota soil surveys
     

Crop productivity index ratings

Crop Productivity Index ratings from the Natural Resources Conservation Service provide a way to compare the relative productivity of soils. For more information, click here.

Crop Productivity Index ratings supersede the older system of Crop Equivalent Ratings (CERs) computed by the University of Minnesota.
 


Contact and update information

This site represents MnGeo's most up-to-date understanding of the status of a variety of soils data for Minnesota. Please send corrections or information on digital soil products not described here to Nancy Rader at MnGeo at: clearing.house@state.mn.us, (651) 201-2489 or 658 Cedar Street, Room 300, St. Paul, MN 55155.

 

Geographic Data Clearinghouse