That may be true where you live, but not here. In my area there are farmers that hire only illegals, some that hire both legal and illegal workers, and some that never hire illegals. The sad thing is the farmers that don’t hire illegals have to compete with those that do.
My business puts me on Farms ALL OVER the Lower 48 United States, Mexico, and Puerto Rico, every day. It is true EVERYWHERE. And New Mexico is one of the worst offenders. Poor land quality and lack of water in the desert Southwest change the outdoor aspect of the business — and that is all. In any location where labor is intensive, illegals are used.