I use organic peat moss in my tub, the girls fight over it when I put new peat moss in.Thank you, Bogtown Chick! I tried responding yesterday but I must have been having computer issues because it wouldn't let me respond. I went out yesterday and purchased an old wash tub, sand, and ash and placed it in their area. One of my daughters and I picked up the hens and placed them in it so they would know what it was. They couldn't wait to get out and wanted NOTHING to do with it. I hope they eventually figure it out and climb in on their own. I think they will at some point as my girls seem to be a little slow. When I first moved them out to their coop last spring, everything I read said chickens will learn to put themselves to sleep within 2 weeks but of course it took mine much longer than that so before they learned, I was out there each night trying to catch them and placing them into the coop. Comical to say the least.
If they don't figure it out, I'll probably dump it directly on the ground and see if that will work. The only problem with that is when it rains.