[Isamu]

If you raise crops or farm animals, you are a farmer.

The USDA is not trying to pull a fast one with the definition of a farmer.

We could have a discussion about farmers that have other jobs and so are part time farming and part time something else. That tends to correlate with less intensive farming like corn and soybeans.

[NoGravitas]

Is a massive agribusiness conglomerate a farmer? Most farmland in the US is "owner operated". But really, that just means it's not rented out by a non-operator landlord, which is the distinction that USDA article makes.