Sorry if this has already been done to death - we're going to build our first coop and run soon and I know we have pests in our neighborhood. We definitely have raccoons, rats, possums and skunks (plus my two crazy dogs). I'd like to bury something around the perimeter as a barrier to tunneling but I'm not sure what's best - will 12" of hardware cloth be enough, or does it need to be deeper or solid? And if I bury hardware cloth, how long before it rusts away? We live in Southern California so most of the year the soil isn't very wet, but I'd hate to do all the digging and then have to do it again too soon.