I don't know why sand is such a default in people's minds when they fill a dust bath. It's almost like an unspoken rule and the first material they go for when making a dust bath. But the reality is that chickens aren't crazy about sand, at all. Some use it, others will resort to it if they have no other option, but a lot of chickens would rather roll around in plain dirt than use sand. Sand is coarse and abrasive and not very comfortable when rubbed against their skin. They much prefer dry soil, peat moss, wood ash and other such materials that are finer and lighter - like dust, as the name suggests, "dust bath". I went with the popular default of sand, too, back when I was setting up my first dust bath, and my chickens absolutely refused to use it. I built different containers to hold it - larger, deeper, wider, etc. Nope. It's not the container, it's the contents. If they like the medium, they'll cram themselves in a shoebox if that's what it takes! Get rid of the sand and give them peat moss instead - you'll see the instant payoff!
It's too much upkeep though, so I've given up on it now and accepted that they'll just dig craters in the run. Their dust bath is so deep that the top of the peat moss is about 1 foot down, and yet they STILL manage to fling it out and empty the dust bath, and then lose interest in it. They love it when I refill it, and prefer that over their dirt craters, but it doesn't last long before they empty it again and I'm just tired of the whole exercise. I don't know how deep it needs to be for the dust to actually stay in the dust bath...
Yeah they always fling the dust bath material everywhere, I just go get more. In the summer they'll usually find some other place to roll in anyhow, so it's mostly for the wetter months around here.
