personally I think my first food plot would be for some kind of winter feed...least if I owned the land, or was gonna hunt/lease it for a # of years...least around us here it seems winter comes and all there is to eat is picked corn left in the fields....vs. the rest of the year there's tons of feed....acorns, corn, beans, etc...
I think if you're the only field around with feed in the winter, you'd attract the deer and hopefully they'd stick around the rest of the year too, but then I'd move to food plots for during the season....