Summary of steps to get extraction of soil data by attribute.

1. I went to the USDA Soildatamart (http://soildatamart.nrcs.usda.gov/State.aspx) and requested a download of soil data by county. This e-mails an ftp link to my e-mail (remember to turn spam filtering off from this account. The data got downloaded to my Mac desktop.

2. Going to the Geocommunicator homepage at BLM, I downloaded the township boundary files. (These, too, come from USDA, it turns out.) http://www.geocommunicator.gov/GeoComm/lsis_home/home/index.htm > Land Survey Information System > download county (upper right corner) > (http://www.geocommunicator.gov/blmMap/MapLSIS.jsp)

Important: turn off pop-up blockers

The data are downloaded and then connected to a base Arc map.

3. It is necessary to extract the soil capability rating from the soils files. The key file is Documents // ArcGIS // soil_xxxxx // tabular // muaggatt.txt. I wrote a python script (MAC Documents/imbook/soil_in097/tabular/getspildata.py which extracts the relevant columns of soil classification in a tab-delimited format for import into a spreadsheet that can then be saved as a dbf.

4. The suitability ratings can then be linked to the appropriate soil data layer.

5. The tabular AOI data can be extracted using "select by attribute" and then using the geoprocessing tool to clip by the selection set. Then the tabular data can be seen on the resulting geodata output layer.
posted by Lloyd at 8:42 PM