Pennsylvania has a long history of protecting its citizens from uninformed recording. Generally speaking, recording someone when they have a reasonable expectation of privacy is prohibited. Audio is particularly controlled, prohibiting the recording of audio in a private setting unless you have someone’s expressed permission or a court order allowing you to do so.
The key is the expectation of privacy. No one should expect to have an expectation of privacy at a public meeting or on a public street, for example. But they should have an expectation of privacy on their own property, in their home, or at their business.
With that as a backdrop, it appears consistent with current law for farmers to expect to have privacy on their own land. That can cut both ways. Some will certainly argue that current law covers this already. Others clearly believe that current law is insufficient.
Unless a court of competent jurisdiction orders it, no one should be able to enter your private property under false pretenses, no one should be able to steal your data or your information, and no one should be allowed to spy on private citizens. If that is happening, it should be stopped.
American citizens enjoy private property rights and a certain degree of privacy. Farmers should be no different.