I'll give an opposing viewpoint from somebody who has a plot too large for the local deer. My plot is about 4 acres and is planted in the Whitetail Institute's "Alfa Rack". A mix of Alfalfa, Clover and Chicory. I think the mix ratio is 60%, 30%, 10% respectively. I don't have nearly the deer numbers some of you have and the deer don't even begin to eat my plot down. As a result it gets tall and stemmy, falls over and generally becomes worthless for feeding anything about once a month. I take care of this by cutting it for hay but if you don't have hay equipment that's not an option and you'd end up having to bush hog it. Even that isn't good because you aren't removing the cut forage from the field and will eventually kill it all as all the dead stuff accumulates over time. The main point here being, don't plant such a big plot that your deer can't keep up with it.
Truf08, you misspoke on one thing above. Alfalfa creates it's own nitrogen the same as clover since they are both in the legume family. Either one only requires a fertilize with a little nitrogen when you plant, then none from that point forward. Practically speaking though, my CO-OP has never had zero nitrogen fertilize so I always use 6-12-12 for any clover or alfalfa field. One time I did get some 0-20-20 or something like that from another source but it was so horrendously expensive that my hands shook when pouring it from the bags and I never used that again. :)