We have a few acres of grass, brush, and woods to free range our flock of general-purpose chickens on. Currently I keep laying ration available to them 24/7, but I have some questions... Do I have to give them supplementary feed? If yes, can I give them a simpler feed than a commercial laying ration and still have them lay well and grow well? Can I feed layers, breeders, and growing meat birds all the same thing? If mixing my own feed, what are the important components and how much? (I know the levels of protein, but what about calcium, phosphorous, etc.?) I'm not looking for a recipe, just some basic pointers.