If you mandate that all meat come from field fed, hay fed sources, with no fertilizer (hay is a great rotational crop), instead of corn or other crops, solved problem.
You know, like the rest of the world does it.
(That is, unless you plan to shoot and kill and exterminate all bison, deer, etc, that would take over any land we leave fallow...)
I ask because I've met Europeans who were convinced that all of their beef was grass-fed, while I've personally seen cattle being grain-finished (and/or fed a variety of supplemental non-pasture-grass feeds like sugar beets) in places like Ireland and Germany. Marketing != reality.
You know, like the rest of the world does it.
(That is, unless you plan to shoot and kill and exterminate all bison, deer, etc, that would take over any land we leave fallow...)