Bravo, somone is thinking outside the box, love this.this is what will make small scale chees production somthing viable to a market, not just a select one at that, for once all hear, see & try, all will take up notice & buy your goods.
What would be good in a field, would have to be afield you take hay off of and use as pasture, this has alwyas been done in years before, dual use of your land.I'd try for a grass, be it timothy, brome or orchard grass along with legumes that are sustainable by themselves, to me colver works, red & ladino, along with trefoil, alfalfa...notwithstanding. Would use what accomidates your pocket book .various species of plants out of the ordinary that animals will consume, wild carrot, wild hops, buttercup, belive it or not various weeds will work well, quack grass, ox eye daisy, red root pigweed, have even seen goats & sheep consume variety of thistles...i'd look further in agronomy books, books that differ from hay production, for as you know weeds are plants growing out of place, ie dandilions, they'll eat them with glee.