When my little chicklets (now 2.5 weeks) get moved to the coop - do I need to provide something for them to have a dust bath, or will they make their own in the grass and dirt? I'm not sure what I'm supposed to do. They'll be in the coop and their run until they are (alot) bigger. And if I do need to provide a dust bath for them, what should I use? Thanks in advance!