DIATOMACEOUS EARTH
by Philip A. Wheeler

If as much time was spent applying diatomaceous earth (DE) to insect infestations as is spent writing about it, the pesticide companies would go out of business However, if someone doesn't keep writing about DE it seems to fade into the background. This could be explained by the fact that Dow, Monsanto, Union Carbide and other manufacturing companies don't really want their profitable poisons replaced by an inexpensive, non-toxic, naturally occurring, low margin material found in 27 countries of the world. Diatoms Are the grass of the oceans and lakes. Just as green grass is the staple food of earth animals, Diatoms (algae) are the food of the ocean or fresh water grazers. These tiny organisms Are protected by a crystal shell which looks like a miniature sand dollar. When DE organisms die, the shells pile up on the bottom to form deposits. These deposits are then mined from underwater beds or from ancient dried lake bottoms.

Once DE is mined, it can be milled or processed into a myriad of types for an even greater variety of uses. Filtering and filler are the two main uses but DE also ends up in paints, cosmetics, drugs, chemical insecticides, etc. Because the milling produces different sized and shaped particles, it is important not to use the filtering type for agricultural purposes .
Filter grind has long crystalline structures which will puncture tissue and injure animals which inhale or ingest it. DE used in agriculture must be milled until it is almost completely amorphous. This means it has no crystalline form left to cause damage to larger organisms Instead, it has small sharp edges which can damage tiny parasites, larvae, on stored grain, in animal manure, on infected plants and in the stomachs of livestock and people.
Since it also has an attractive mineral composition, DE users have reported five distinct uses on the farm: grain storage, deworming, mineralization, deodorizing/absorption, and insecticidal dusting. Each use has its own folklore, facts and fiction associated with it so each will be discussed.
APPROVED FEED ADDITIVE
The EPA has approved DE as an additive in feed for use as an anti-caking agent and has exempted it from tolerance requirements as an inert, inactive ingredient in chemical pesticides. Any uses other than those presented here are strictly reports of what farmers have done with the material.
PARASITE CONTROL
DE has been used for at least two decades as a natural wormer for livestock. It is believed that the DE scratches and dehydrates parasites. Some scientists believe that the DE is a de-ionizer or de-energizer of the worms or parasites. Regardless of the method of operation, farmers report definite control. For effective use, the DE must be fed long enough to catch all the newly hatching eggs or cycling of the worms through the lungs and back to the stomach. A minimum of 60 days is suggested at 2% of dry weight of the grain ration. Caution: do not give to very small pregnant animals such as cats, guinea pigs, etc. and do not feed continually to babies or very small adult animals such as cats, hamsters, etc. The material may be fed on a continuous basis to larger livestock for continuous parasite control and mineralization which is the next major use.
MINERALIZATION
If you began feeding DE to your poultry or livestock and noticed a gain in production, what could the gain be attributed to? The obvious answer would be that the DE reduced the parasite population which resulted in decreased stress on the animal and increased food assimilation. But what about the "mineral" content of the DE? If oyster shell meal provides calcium, then finely ground DE may also provide a broad-spectrum of naturally occurring chelated minerals. These include calcium, magnesium, iron, phosphate, sodium, titanium, potassium and others. Numerous reports of gain have been reported when adding DE: to a ration. With lack of mineralization in modern grains, it isn't hard to conceive of mineral benefits from a finely ground natural mineral product. An Alabama study on hogs showed complete stopping of wood feeder chewing when DE was added to the feed ration. Feeding at 2% of grain ration can take care of both deworming and mineralization. Most livestock will acquire a "taste" for the mineral if a small amount is mixed in with other feed. After acquiring a "taste" for DE they may take it free-choice.
DEODORIZATION/ABSORPTION
The third major farm use can be an added benefit from the first two uses. Deodorizing and absorption are natural functions of DE. These will continue to happen as undigested DE passes through with manure. Reduced fly hatching is usually observed in manure from livestock fed DE. Some dairy and hog farmers are also spreading it in bedding (for odor and moisture control) in addition to that coming through the manure.
FLY CONTROL/INSECTICIDE
Fly control is a major problem with livestock operations. DE can be placed in tightly woven burlap bags and hung in doorways. Livestock will be attracted to it and work the bag until their heads are covered with powder which repels flies. In closed areas, DE can be fogged with hand cranked or electric foggers to wipe out flies. Livestock need not be removed and contamination of milk or feed is not a concern. Since the DE "kill" is always mechanical in nature, it is important that the material come in direct contact with the insect. Mixing DE with things flies are attracted to around the farm may cause them to ingest DE in their attempts to eat the attractant. Besides fly control, DE can be used as an insecticide on most crops. In 1943 the USDA found that DE had an 86% mortality against pea weevil. On California cotton fields, DE was found to be more effective than insecticides and the yield was substantially increased (Tucker, 1978). Other tests indicate that DE is effective in controlling aphids, brown mites, red spider mites, twig bores, oriental fruit moths and coddling moths in orchards (Alien, 1972: DeCrusta, 1979). Field use of DE had several problems Not sticking to the vegetation is the main one. Apply DE when plants are moist from natural or artificial sources to aid sticking but re-application is usually necessary after a heavy rain. Putting a negative electrostatic charge on the DE has greatly increased in adherence to leaf surfaces. One company which has since gone bankrupt perfected an electrostatic applicator but widespread use never occurred. Adding an attractant may also be useful here and several patents have been issued for that purpose.
GRAIN PROTECTION
The last use to discuss is grain and flour storage. DE offers the only easy answer to chemical contamination of stored grain. Irradiation could be used, but cost and negative health effects make it very undesirable. This writer has kept wheat, oats, and spelt in open bins for two years or more with no insect damage by applying DE at approximately 7 pounds pet ton of stored grain. The DE was sprinkled into the auger by hand As an examination of its effectiveness, it was compared with malathion and untreated grain on 1,000 bushels of wheat by the Agricultural Research Service of the USDA. After 12 months storage, the DE treated material had 15 insects compared to 4884 for malathion and 16,994 for untreated. Although 7 pounds of DE may lower the commercial grade of wheat immediately after treatment, the wheat maintained its grade longer than other treated or untreated grain. Flour yielding and bread baking qualities are not affected. The new patents allowing DE to be used effectively at 1 to 2 pounds per ton instead of 7 pounds should eliminate any grade deterioration problems. Recent grain board tests in Canada have proven in the field what the patents claimed on paper, i.e. DE protects stored grain without contaminating it. DE is not the same. Differences have accounted for large variations in past testing on DE as an insecticide which has slowed the universal acceptance of DE for that purpose. This writer prefers fresh water diatoms to sea types for several reasons. The bio-activity seems to be better and the health ramifications of breathing the fine white dust seems to be almost negligible because of its 99% plus amorphous structure compared with a higher percentage crystalline structure. Since we now have electronic testing equipment available it pays to "check it out" before buying and using any DE. Reprinted by permission of ACRES USA, INC., Kansas City, Missouri Nutritional Research Assoc. Inc.'s
FOSSIL FLOUR is a non-treated, non-milled, non-calcined fresh water form of Diatomaceous Earth. It consists of microscopic fresh water diatoms which were deposited millions of years ago and have since fossilized. Under microscopic examination each particle looks like a tiny glass spear which pricks the outer skin or coating of insects, worms, maggots, etc. causing them to dehydrate and die. The product is a fine powder, white to gray in color. Diatomaceous Earth is approved for use as an anti-caking agent in livestock and poultry feeds. Nutritional Research Assoc., Inc. makes no claims about diatomaceous earth other than for approved uses. Test results (University of Illinois) in 1966 show that the use of the product does not harm animals or leave residues in milk or meat.