Diatomaceous Earth—Let Long-Dead Organisms Work for You

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DE is a desiccant that dries out hard-shelled insects that contact it directly. A waxy protective coating on the outside of insect bodies prevents moisture loss.

Diatomaceous earth (DE) destroys this waxy layer, killing cockroaches, silverfish, slugs, ants, fleas, beetles, and many other insects.

Around 300 million years ago, countless numbers of minute one-celled organisms called diatoms existed in the oceans.

They were constructed of tiny shells made of silica they extracted from the water they lived in. They converted the silica into silicon dioxide.

When the diatoms died, their microscopic shells were left on the sea floor.

Through the centuries, these shells eventually collected into deposits, sometimes thousands of feet thick. When the waters receded, the deposits were eventually covered and the shells fossilized and compressed into a soft chalk-like rock.

Producing Diatomaceous Earth

DE is quarried, milled, finely ground, passed through a screen and put through a centrifuge to turn it into a fine talc-like powder. This powder can be safely handled with bare hands and fed to animals. Yet it kills insects on contact.

Proper milling cracks apart the diatom skeleton, leaving microscopic silica needles. Sharp and hazardous to the insect, these needles are harmless to humans and other warmblooded animals. The tiny size and razor-like construction of a DE fragment is just right to disrupt the life of insects.

These minute sharp particles are also taken internally by certain insects and interfere with their breathing, digestion and reproduction.

DE is a non-toxic material containing minerals that are useful to the soil, such as manganese, magnesium, iron, titanium, calcium and silicon.

Using DE

It doesn't work when wet. Because of this, only use them in dry areas, and replace after every rain. Even if kept in dry locations, the material will eventually absorb moisture from the air, so you'll have to keep using it in the garden.

When placed in a closed, dry space, it will remain active under normal conditions for about 2-3 weeks. During the humid summer months, the DE will probably not be effective longer than one week. Use small amounts and re-apply often.

Place the material in a duster or a flexible bottle that has a narrow nozzle less than 1/4" in diameter. Apply a thin coating of the material. Many small puffs of dust are better than one large application.

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