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I'm building a GIS for a large-scale family farm. We don't have a lot of resources to devote to this, as it's a new part of the farming operation and therefore viewed with some reserved skepticism. I'd like to start building prescription maps for fertilizer, etc applications, which means I need to import some soils data.

My question relates to the USDA SSURGO database download. To my understanding, in order to import this data into GIS I would need MS Access, which we do not have. So is there another way to access this data while bypassing the Microsoft empire?

I've read a little bit from OSGeo about using PostgreSQL and/or PostGIS, but I don't quite understand how it works. I know this alternative is not as easy as the Access route. Would this be a good option for me?

As a side, I think I'd be interested in PostgreSQL for managing our spatial data. We don't have a lot yet, so the file system I have set up locally works for now, but I think it could be useful later on.

  • I've worked with SSURGO data in ArcGIS without using MS Access. Also, ArcMap will open tables in an .mdb that is not a personal geodatabase. – klewis Oct 27 '16 at 22:29
  • Look into the newer gSSURGO format, which uses file geodatabases – Bjorn Oct 27 '16 at 23:21
  • How large of an area are you looking at? Also, what types of GIS are you using. Do you have Esri products or are you more likely to use something like QGIS? Also, what type of soil information do you want? Basic stuff is easier to get out of SSURGO than some of the things in related tables like grain size, but it can all be done. Depending on your background, PostGIS may be biting off a lot. Do you have any database experience with MySQL or SQLite? – Nate Wanner Oct 28 '16 at 0:03
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    FYI - the MS Access database created with the SSURGO template is only the tabular info. They provide separate shapefiles that hold the spatial data and can then be linked to the tabular data in GIS. – Nate Wanner Oct 28 '16 at 0:30
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Yes, there is another way to access SSURGO data without Microsoft Access, you can use the Open source options you've already looked into PostgreSQL and PostGIS. Here is a good resource here. They provide access to their composite survey which allows for you to connect with your Open source database using SSH.

If this is a good option for you, than that would depend on how comfortable in using Open Source Software (OSS) and running queries using Standard Query Language (SQL).

You could alternatively use the United Stated Department of Agriculture (USDA) Web Soil Survey web map to view the data for your area of interest.

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I recently downloaded the SSURGO data for Ohio. It came as compressed zip files by county. Within each county zip archive were tabular and spatial data. The tabular data is in the form of CSV text files, and the spatial data as shapefiles. I assume you will start with a similar download.

The NRCS SSURGO website has metadata on the datasets. The SSURGO Metadata - Tables and Columns Report contains information on each of the tables. The text file names are sometimes a bit different than the table names in order to keep text file names at 8 characters, but aren't too hard to correlate. Because the text files do not have header rows, the tables and columns report will tell you the order of data in each row (the columns in the report are listed in the same order as the fields in the text file).

The data model diagrams on the SSURGO website and the relationship report will tell you how all of the tables relate to each other. In the upper right corner of diagram 1 you will see some tables in blue that match the shapefiles downloaded. You can use the indicated fields and relationships to pull the data you need.

Since you are discussing PostGIS and trying to avoid Microsoft, I am assuming you do not have Esri products. If you haven't already, I suggest you look into QGIS. By importing the shapefiles and tables (as CSV) both into QGIS, you can create joins under the layer properties to access the information you want from the SSURGO tables. This way, you avoid MS Access as you desire, and can start to work with the data a bit before going into PostGIS. This may also be a good way to process the data before import to Postgres/PostGIS.

When you are ready to put all this into PostGIS, I suggest you look at this post. There is some good information on it. I've been working on a state-wide download of SSURGO data that includes all of the auxiliary tables. I hope to add links to some of the SQL and scripts I've used in the future, but they aren't quite clean enough to share yet.

FYI - the primary advantage to using the MS Access templates are that you don't need to figure out the field order yourself, and there are some queries already created that relate information between the various tables. You could then connect to the database the same way I discussed connecting to CSV text files, and create a join between the shapefiles and database tables (vs. shapefiles and text files).

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