The important query I need to run is this, given an (x, y) of say (1551459.363, 1909201.537):
But coordinates are only useful if you know what coordinate system they belong to. The documentation is rather sparse, but I found this information:
The CDL is processed using the Albers Equal-Area Conic Projection with a spheroid of GRS 1980 and datum of NAD83. The downloadable zip files from the SARS website and CropScape are offered in the native Albers projection.
In order to conform to Geospatial Data Gateway technical specifications, any CDL data downloaded through the Geospatial Data Gateway is reprojected from Albers to the dominant Universal Transverse Mercator (UTM) zone with a spheroid and datum of WGS84. The one exception to the UTM projection is for Wisconsin. Wisconsin is projected using the Wisconsin Transverse Mercator (WTM) projection. This WTM projection is based on the 1991 adjustment to NAD83, and is called WTM83/91.
So I headed over to PostGIS to look for a match (hopefully this wasn't too narrow):
SELECT * FROM spatial_ref_sys WHERE srtext ILIKE '%DATUM%83%SPHEROID%80%' AND srtext ILIKE '%albers%';
I found 17 matches, but the projections are all regional like "Texas Centric Albers Equal Area".
How do I boil this information down to the correct SRID?