My chickens have worn down their 25x25 pen to just bare dirt and mud (and alot of manure). This spring, I'd like to seed it with something that will sprout and grow. I'll keep them out of it, of course, until it's done growing and ready for more trampling. What sort of grain/grass would people recommend that they would like to eat? I think I should just be able to scratch up the dirt real good, sprinkle in the seed, and water well. Any tips?