Fact Sheets And Publications

There are several methods by which you can define the area of interest (AOI). For example, you can retrieve information on all soils in a county using the “Soil Survey Area” tab in the “Quick Navigation” menu on the left side of the screen (Figure 2). To set the AOI for a whole county:

1. Select the state  

2. Select the county 

3. Click the radio button under “name” to select the appropriate county soil survey

4. Click the “Set AOI” button at the top of the dropdown menu.

The selected AOI will be outlined in blue (Figure 3).

• The AOI can also be set for a smaller region by using the shape tools to select a specific area. An easy way to do this is to navigate to a specific address using the “Address” tab in the “Quick Navigation” menu on the left side of the screen and then draw the AOI (Figure 4). To draw an AOI based on a specific address:

• Type the address

• Zoom in or out using the tools on the map view (magnifying glasses with + or -) and pan by using the hand tool to get to the correct land parcel

• Select the desired area using the AOI tools in the map. There are two AOI selection tools, one for rectangular shaped (left) and one for customized shapes (right).

The AOI can also be set for a smaller region by using the shape tools to select a specific area. An easy way to do this is to navigate to a specific address using the “Address” tab in the “Quick Navigation” menu on the left side of the screen and then draw the AOI (Figure 4). To draw an AOI based on a specific address:

1. Type the address

2. Zoom in or out using the tools on the map view (magnifying glasses with + or -) and pan by using the hand tool to get to the correct land parcel

3. Select the desired area using the AOI tools in the map. There are two AOI selection tools, one for rectangular shaped (left) and one for customized shapes (right).

Generating a Soil Map

Once an AOI is selected, the “Soil Map” tab is used to open the soil map view (Figure 5). The orange outlines on the map depict the individual soil map unit boundaries. Each map unit is assigned a map unit symbol, which is defined in the map unit legend (located on the left). The legend shows the map unit name (based on the predominant soil series), the acres of that map unit in the AOI, and the percentage of the AOI covered by that map unit.

Be aware that if your AOI is very small, you may receive a warning that “the soil survey may not be valid at this scale”. If you receive this warning, it is an indication that the accuracy of the map may be lower. Use caution in interpreting data if continuing at small scales or consider expanding the AOI to a scale that is supported by the data.  

Obtaining Detailed Soil Information

More information about the soil map units that are located within the AOI is available under the “Soil Data Explorer” tab. Information about land use suitabilities, soil properties, and other information is available in the Soil Data Explorer tab. Here, we provide some examples of the type of data you can obtain.

Suitabilities and Limitations for Use

The “Suitabilities and Limitations for Use” tab of the “Soil Data Explorer” provides ratings and suitabilities for a variety of land uses. Here you can determine if your soils are suitable for a variety of land classifications (e.g., soil capability class, soil moisture class, etc.) and land management options (e.g., dwellings with basements, septic drainfield, irrigation, roads, etc.).

For example, the “Irrigated Capability Class” option under the “Land Classifications” dropdown (located in the menu on the left side of the screen) provides information about the suitability of soils for production of field crops with irrigation. Ratings range from class 1 to class 8, with class 1 being soils with few limitations for crop production. To generate a soil map with ratings for irrigated capability class (Figure 6):

1. Select the “Land Classification” from the dropdown menu

2. Select “Irrigated Capability Class”

3. Select “View Report”

4. Click on the “Legend” tab to the left of the map to see the layer properties

Soil Properties and Qualities

The “Soil Properties and Qualities” tab of the “Soil Data Explorer” provides information about various soil chemical (e.g., cation exchange capacity, electrical conductivity), soil health (e.g., bulk density, organic matter), and soil physical properties (e.g., available water capacity, hydraulic conductivity), as well as soil erosion factors, soil qualities and features (e.g., depth to bedrock, hydrologic soil group), and water features (e.g., depth to water table).

For example, the “Depth to Water Table” option under the “Water Features” provides an estimation of the depth below ground surface to the seasonal high water table (i.e., saturated zone in the soil) based on the presence of soil features that suggest saturation (Figure 7). To generate a soil map showing the depth to water table for each map unit:

1. Select “Water Features” from the dropdown menu

2. Select “Depth to Water Table”

3. Select “View Rating”

4. Click on the “Legend” tab to the left of the map to see the layer properties

Soil Reports

The “Soil Reports” tab of the “Soil Data Explorer” provides detailed information about the soils in the AOI, as well as various soil properties and suitabilities. 

For example, the “Soil Map Unit Descriptions” option in the “Soil Reports” tab provides more detailed information about the soil series included in the AOI (Figure 8). To obtain information about the dominant and minor soil series in the AOI”

1. Select “AOI Inventory” from the dropdown menu

2. Select “Map Unit Descriptions” 

3. Select “View Soil Report”

Creating Printable Reports

There are various ways you can create high quality printable reports including the maps that were generated for your AOI.  One option is to select the “Printable Version” button at the top right hand corner of the map. This option will generate a downloadable PDF for the specific information you are currently viewing.

If you want to download a variety of maps, a more efficient way is to select “Add to Shopping Cart” in the upper right corner as you select data. This option will consolidate all of your maps into the shopping cart. You can then navigate to the “Shopping Cart” tab and generate a single printable PDF report with multiple maps.

Summary

These instructions were written to help consultants and farmers start using the WSS to retrieve information from the NRCS SSURGO databases. The WSS is a comprehensive tool with options that extend well beyond the scope of this fact sheet. More comprehensive instructions for using the WSS are available via the WSS website. There are also a variety of other tools available to retrieve SSURGO data including the resources created by the California Soil Resources lab and various GIS platforms.

References

Soil Survey Staff, Natural Resources Conservation Service, United States Department of Agriculture. Web Soil Survey. https://websoilsurvey.nrcs.usda.gov/app/

University of California, Davis, California Soil Resource Lab; University of California, Division of Agriculture and Natural Resources; Natural Resources Conservation Service (2019). SoilWeb. University of California; USDA-NRCS. Dataset. https://hdl.handle.net/10113/AA23078
 

About the Authors

Amy L. Shober (corresponding author), Professor and Extension Specialist, University of Delaware, Newark, DE (ashober@udel.edu)

Rebecca Rothweiler, Nutrient Management Program Assistant (former), University of Delaware, Newark, DE
 

About the Publication

Original publication date: 2016
Revision date(s): 2025
 

Peer Reviewers

Lyndsie Mikklesen, Extension Agent, University of Delaware Cooperative Extension, Georgetown, DE

Sydney Riggi, Extension Agent, University of Delaware Cooperative Extension, Dover, DE