Files for soil texture data

Data set reference code -- 1995-0795

To accommodate users with a variety of GIS software, the data giving the dominant soil texture class for each of the 11 standard layers are available in several different formats. The files needed by each of the types of user below are described separately. NOTE: Most of these files have been compressed using the GNU gzip program, as indicated by the .gz file extension. Users who do not have access to the gunzip decompression program can request that files be uncompressed prior to transfer via ftp. In some cases, however, the uncompressed file may be very much larger than the compressed version, greatly increasing file transfer time.

Arc/Info polygon file users

The orginal STATSGO mapunits for the 48 states have been merged into a single Arc/Info polygon (vector) coverage. The dominant soil texture class at 11 standard layers and the mean depth to bedrock data for each mapunit are given by auxiliary INFO tables, which may be RELATEd to the mapunit coverage using "MUID" as the relate item. The needed files are
mu_poly.e00.gz (101 Mbyte, uncompresses to 269 Mbyte)
Mapunit polygon coverage in Arc/Info EXPORT format.
domtextcode.e00.gz (130 kbyte, uncompresses to 735 kbyte)
INFO table giving numeric code for dominant texture class for each standard layer of each mapunit, plus mean depth to bedrock in cm., in Arc/Info EXPORT format.
domtextname.e00.gz (126 kbyte, uncompresses to 725 kbyte)
INFO table giving standard NRCS abbreviation for dominant texture class for each layer, plus depth to bedrock, in Arc/Info EXPORT format.
textclass.e00
INFO table giving numeric code, abbreviation, and full name for each soil texture class.
stdlayer.e00
INFO table defining the 11 standard soil layers for which the dominant soil texture classes were computed.

Arc/Info grid file users

The mapunits have been gridded at 30-arcsec cell size. The value attribute table (VAT) for the Arc/Info grid listed below contains the mapunit indentifier, MUID, the mapunit serial number, MUSERIAL, the numeric code for the dominant texture class for each standard layer, the standard NRCS abbreviation for the dominant texture class, and the mean depth to bedrock.

Warning -- The uncompressed version of the grid file below is very much larger than the compressed version.

domtextgrid.e00.gz (10.5 Mbyte, uncompresses to 192 Mbyte)
30-arcsec grid of mapunits, including VAT, in Arc/Info format.
textclass.e00
INFO table giving numeric code, abbreviation, and full name for each soil texture class.
stdlayer.e00
INFO table defining the 11 standard soil layers for which the dominant soil texture classes were computed.

Other users of gridded data

The 30-arcsec gridded data are also available as a three-dimensional array of 8-bit binary values, in band-sequential (BSQ) form. All data for the upper-most layer are given first, followed by all data for the second layer, and so on, until the 11-th layer is complete. Within each layer, the data are organized by horizontal rows, with the top (northern-most) row first, and the data for each row starting at the left (western) end of the row.

The array contains 11 layers, each consisting of 2984 rows of 6936 values each. Code for reading the binary array is available in Fortran 77 and C.

Warning -- The uncompressed version of the BSQ file below is very much larger than the compressed version.

layertext.bsq.gz (14 Mbyte, uncompresses to 227 Mbyte)
Three dimensional array of one-byte numeric codes for each grid cell and soil layer.
textclass.ascii
Table giving numeric code, abbreviation, and full name for each soil texture class.
domtext.ascii.gz (112 kbyte, uncompresses to 829 kbyte)
Table giving, for each STATSGO mapunit, the mapunit ID, mapunit serial number, the NRCS abbreviation for the dominant texture class in each layer, and the mean depth to bedrock in cm.
stdlayer.ascii
Table defining the 11 standard soil layers for which the dominant soil texture classes were computed.

Local users on the ESSC network

The filesystems containing the datasets are cross-mounted on the local ESSC computer network. Local Arc/Info users may find it more convenient to copy necessary files directly to their own workspaces using the Arc/Info COPY and COPYINFO commands. The needed directories and files (under directory $DSREF/1995-0795/) are
domtextgrid
Arc/Info grid representation of mapunits; the dominant soil texture class information from tables DOMTEXTCODE and DOMTEXTNAME is included in the VAT for this grid.
../mapunits/mu_poly
Arc/Info coverage containing polygon version of mapunit boundaries.
info!DOMTEXTCODE
INFO table giving numeric code for dominant texture class for each standard layer of each mapunit, plus mean depth to bedrock in cm.
info!DOMTEXTNAME
INFO table giving standard NRCS abbreviation for dominant texture class for each standard layer of each mapunit, plus depth to bedrock.
info!TEXTCLASS
INFO Table giving numeric code, abbreviation, and full name for each texture class.
info!STDLAYER
Table defining the 11 standard soil layers for which the dominant soil texture classes were computed.
Last change: 2006 Apr 14, R. A. White / raw@essc.psu.edu