Economics are quite nice...they fix themselves as long as government doesn't mess them up.

Removing productive farmland from production is simply stupid.   Crops are not like oil, which if not used today, can be used tomorrow instead.  A piece of farmland can produce a crop every year.  That growing season cannot be "saved" for later.  If you don't use it, it is wasted.  Gone forever.  Never to be recovered.  Waste is not good.   Just like hiring a workforce and then deciding to not have them do anything... m  If there is enough production to meet needs, then the price will go down so that someone finds something to do with the "extra" production. Hopefully something useful, or else some of the productive land will go below cost and will come out of production because it is not profitable to use.   

Any sort of external forces on the market, be they price controls, production controls, monopolistic forces, or other non-competitive factors interfere with proper and efficient operation of the market and have the effect of reducing the overall well being of the society.