I just completed construction of my chicken tractor and have been pulling my 7 chickens around the yard. Until now, I've been giving them chicken feed daily. Now that they'll be grazing on my lawn and pasture, do I still need to give them a bowl of feed? How can I tell if they are getting enough from the earth? Do they eat grass, clover, weeds? I have a wide variety of grasses in different areas. Any advice on how to use a chicken tractor and possibly supplement with feed will be appreciated. I would like their diet to be as much "off the land" as possible.