Hay is usually made from clover or alfalfa (the plant,not the kid). If they were blooming at the time,the dried flowers would add another dimension. Not to be confused with straw,hay is still greenish,but dried whole plant material. Straw is the stalks of wheat after the grains have been removed.
So you may get something like cilantro with a bit of sweetness.
Everything works if ya let it-Roady(meatloaf)