They have tried that "burn ban" thing before in the past here, right in the middle of when burning needs to be done.  I don't think they consider the economic cost of their actions, which stands to reason because it falls on agriculture, not on government.  Most went ahead and got done what needed to be done but there was much bitching and moaning and may have been a few people fined unnecessarily....one I recall was a neighbor burning a brush pile in the middle of a half section of land which was all clean tilled, on a calm night....some rocket scientist decided to write that all burns had to be completed before dark...first impossible...brush pile takes longer then that to burn, and second stupid... because that's when the wind doesn't blow.    I've heard stories of local governments pulling that in rice country...but they warned people for the first offense....so of course that means you had to get 5000 acres ready and do it all at once "the first time"...obviously a stupid idea, but what do you expect when the government substitutes rules for good sense?   I just don't see much in the way of farmer's stubble burns get out of control...the so-called "controlled burns" that turn into problems are the ones being done by amateurs who don't know what they are doing and do not have the sense or equipment on site to do it safely.