This is an old thread, started in 2007. I don't usually like to add to older threads, since the OP is often long gone or has had his/her questions answered long since, but since it's been resurrected, I'll just jump in with my 2cent's worth.
DE and Stall Dry are not the same thing, although Stall Dry does contain DE. DE, or diatomacious earth, is composed of the fossils of tiny little critters called diatoms. It is basically silica and has many sharp sides and edges in each grain. It kills small, soft bodied creatures by puncturing their soft outsides and allowing their "juices" to run out. Many people use it and swear
by it for mite and lice protection. I swore
at it. I was a huge proponent for a long time, until one day I realized that I was out there adding it to my chickens' dust bath, wearing a bandanna over my face. Why? Because the bag cautions against using it without breathing protection. What it does to kill soft bodied insects it also does to bronchial tubes and lungs. Wait a minute - it's not safe for me, way up here, to breathe in this stuff but I'm putting it in here for my chickens to wallow around in and stir up? They are IN it all day and all night, they are closer to the harmful dust than I am and they have delicate respiratory systems. And the dust bath wasn't the only place I was using it...I sprinkled it on the floor of the coop, on the roosts, and in their nest boxes as well. What was I doing?? The bag of DE got regulated to what it was designed to do - kill aphids in my vegetables and flower beds, but never again did I subject the chickens to it. The second point about DE is that in true deep litter, those little organisms are really needed to help break down the materials used in there...why would I want to add a product that kills them?
Stall Dry contains a small amount of DE mixed with of calcium bentonite. A similar product is Sweet PDZ, which absorbs moisture and neutralizes orders using Zeolite.
If someone is contemplating using deep litter, the
first thing that has to be understood is the difference between deep litter and deep bedding. When I did a clean out of my setup after a year, the golden pine shavings I'd started out using looked like, well, yellow and/or gray pine shavings. They didn't break down very well, still retained their shape even deep down in the litter, and although they worked very well to provide a soft surface that absorbed liquids and odors, they didn't truly break down. I had deep bedding going. It was working, but it wasn't what I wanted. During the clean out, I scooped out wheelbarrow after wheelbarrow of old pine shavings, and they still LOOKED like pine shavings.
So with the advice of
@Beekissed, who is a genius at this stuff, I decided to switch to dried leaves, chopped up straw, grass clippings, pulled weeds, garden refuse, pine needles, wood chips, and learned to watch that balance between greens and carbons. I left all the little twigs and such in the leaves when I raked and bagged them up. Those provided air spaces in the litter, as did the occasional handfuls of pine shavings I still tossed in periodically. I had to start sourcing leaves from other places besides my own yard. I have many huge trees, but they are all the same trees...which meant the leaves were all the same basic shape and size. So at first I had a matting issue with them, but once I added leaves of various sizes and shapes it was much better. The last lesson I had to learn was NOT to clean to the ground. I had to think of deep litter as sourdough starter - leave a little of the original stuff on the ground to kick start the new stuff.
I had no issues with flies, and any odors meant that I wasn't flipping (that's flipping, not stirring) the litter like I should be, the litter had gotten too wet (resolved by adding more dry stuff) or my carbon/green balance was off and I needed more leaves. I just dumped a bag of leaves or whatever in there and let the chickens do the rest. This is what my deep litter looked like when I did a clean-out after over a year - if I remember right it was probably closer to 2 years. As you can see the in the second shot, I didn't have to dig down very far to get to that good, rich stuff for my garden.
