Definition: Diatomaceous earth is the powdered remains of diatoms, which were ancient, sea dwelling algae. While it feels like a fine, soft powder to humans, it is composed of millions of tiny, jagged edges that spell doom for a wide variety of garden trouble-makers. Diatomaceous earth works by cutting the pest, causing it to dry up and die. In the case of slugs and snails, DE can be sprinkled on the ground and on plants they eat, and the sharp edges will cut them as they slide across the diatomaceous earth. It is also effective if the pests consume it, since it will abrade them internally, causing eventual death as well. A mask should be worn at all times when working with DE, because it is very irritating if inhaled. It should be used sparingly, since it is equally damaging to beneficial insects.
Also Known As: DE
Common Misspellings: diatomacious earth
Examples:To keep slugs from devouring young carrot foliage, sprinkle that area of the garden with diatomaceous earth.