How many acres would a person need to go feral?

[Baby Lee]

I guess I define feral in a manner incompatible with restrictions on conduct.
If I'm going to go out and fend for myself, I'm going to make the optimum use of everything in my domain.
Who's gonna stop me from farming?
Who's gonna stop me from domesticating wildlife? There certainly isn't anyone there to save my ass if I try to domesticate something that doesn't have my interests at heart.

Rules connote a connection to some civilization out there monitoring and enforcing them.
That's not feral.