Hi there, this is Julie7's daughter, Kimmie.
I raise all different kinds of birds, from poultry, to game birds, waterfowl, and have now acquired turkeys. I wanted to say that even during the summer, your hens will need a layer ration, that has the appropriate amount of protein and vitamins in order to keep your hens in top laying shape. Free-ranging is an excellent thing to do with your birds if there aren't any predators around. Keep in mind though, dogs aren't the only predators. If you have hawks or crows around, they tend to prey on smaller birds like chickens. Raccoons, moles, minks, and other things like that will make a meal out of a chicken, too. The hens should roost in the tree, but make sure they have nesting boxes around to lay in. A small shelter wouldn't be a bad idea, especially for winter, or just for safety reasons to lock them up at night. Also, it's not a bad idea to have crushed oyster shells for calcium, to develop the egg shell. Or in place of oyster shell, you can keep the egg shells you use and boil or bake them for a few minutes, crush them up and feed them back to the hens. Keep in mind though, the price of eggs is going up because the price of feed is rising. Five or six hens wouldn't cost too much to feed, but the more you have the more feed is needed. If you have any more questions, feel free to e-mail me at apostolic.princess@yahoo.com. Chickens are really a joy, I love mine and wouldn't trade them for anything... but there's also quite a bit of work involved. Good luck!