I'm on the hunt for field boundary coordinates in the US in the form of GeoJSON, a Shapefile or any structured format that I can use to overlay on a map.
I've tried looking at the US Department of Agriculture but can't seem to find it.
Not sure I'm using the correct terminology for find such data.
When I worked at NRCS, we used CLU layers, which followed tracts of fields. I don't see them at http://datagateway.nrcs.usda.gov/. However, if this is a serious request for data and you are willing to put some time into it, you should give your local county field office (either NRCS or FSA) a phone call. They are usually happy to help, and if you ask to talk to the state GIS coordinator, they might be willing to help with coverage across the entire state (we restricted field office to county-level access). I don't know if they data is classified in any way. Again, if this is a serious enough request, reach out to those guys. They are always willing to help if they can (in my opinion).
I believe FSA maintains the CLU layers, but NRCS uses them for planning. The two branches are often entertwined in their GIS data.
CLU isn't available to the general public. It's considered PII now.
None the less. It's doesn't cover all ground, just those involved in USDA programs. Plus, the boundaries don't always match up with what's actually going on the ground.
For example, a producer decides to crop one part of a field in beans and the other in corn. The CLU boundary may not reflect that split.
There is a data crop layer NASS produces. A raster product which covers all of the US.
A little bit late but here is the link to the data crop layer that the NASS produces for the U.S.