Diatomaceous Earth -
Diatomaceous Earth is primarily used for the control of external parasites, and as a wormer when using food grade DE. Diatomaceous (die-uh-toe-may-shus) Earth, isn't dirt or earth, not even colored like it. It consists of the broken up shells of tiny critters, called diatoms, that lived long ago and died in groups so massive that they can, today, be mined and bull-dozed. "DE", as diatomaceous earth is abbreviated, has the neat quality of killing insects. It's perfect for natural insect control. (Unfortunately, it kills good ones, like bees and ladybugs, too, so its use shouldn't be indiscriminate.) It is 100% ecologically safe to the environment and non-poisonous to man and beast. In fact, if you've eaten anything made with flour (like Bisquick), you've eaten DE. It's used in commercial grain storage as a means of natural, poison-free, insect control.
Worming -
* Add 2% D.E. to your feed to reduce, or eliminate internal parasites and worms.
Delousing -
* You can dust your birds to help control external parasites like red mites, and lice. You will also need to spread this liberally on roosts, bedding areas, and dusting spots. Take care not to inhale the dust, as it can cause lung problems.
Now there is some disagreement on weather DE works as a wormier or not and I my self don't rely on DE as a sole worming agent.
I much rather use a product like Ivermectin as a wormier and a secondary agent for mites and lice.
I do use DE mixed with wood ash in the pens as a dust before I put bedding and or sand down.
In the nest boxes, I us a mixture of DE, Wood Ash and Sand at the bottom of the nest box along with Tobacco Stems as the nesting material.
*Note -
The Sand I refer to is Builders Sand and is not Play Sand. Play Sand is much to fine and will just pack and cause a mess where Builders Sand is coarser and has less tendency to pack.
Tobacco Stems are used as a nesting material and has a benefit in that it helps keep down lice and feather mites.
Chris