We have a couple new to us hens (7 weeks old) and we haven't seen either take a dust bath. It's been colder out/not a lot of sun. Is this something that takes a little time for them to get comfortable and do? We have a bath set up in the coop and the coop floor is dirt, but no takers yet...any thoughts on how to encourage this? Also, whats the best flooring for a coop? We're worried our dirt is a little too clay-like.