Reading the research on native grass fertilization is interesting, but disappointing.  Looks like it really isn't a very good grass composition to fertilize.  We don't have brome or fescue, our cool weather grass that is growing like crazy now is cheat. 

There have been a couple of people I know who have tried growing corn on subirrigated ground here and they gave up on it. I have heard of some crazy alfalfa yields on it though, one person got 5 cuttings last year during the severe drought.  But it tends to stay way too wet if you get rain and tractors get stuck bad.  That said I would love to try corn or alfalfa sometime in the future if I ever get some farmground to justify the equipment, otherwise it isn't all that cost effective to buy equipment for 30 acres of ground.