I happened upon a most amazing picture. Who knew that diatoms were such a lovely lot?
Organic gardeners know that diatomaceous earth is useful for insect control, but I was surprised at its uses. There are food grade and pool grade, the latter being poisonous, but the food grade is good for worming, and to get rid fo fleas. I didn’t know that! Precautions of not being downwind of it, as it is drying to the eyes is something to remember.
Diatomaceous earth consists of the remains of microscopic one-celled plants (phytoplankton) called diatoms. They are fossilized remains of these tiny things from long ago oceans and lakes. These deposits are mined from underwater beds or from ancient dried lake bottoms thousands of years old. diatomaceous earth has an unlimited shelf life provided you keep it dry. – Info from Wolfcreek Ranch


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“[FOOD GRADE] is not the same thing as the DE used in swimming pool filters. Pool grade DE is Diatomaceous Earth produced for pool filters and it is treated with heat, causing the formerly amorphous silicon dioxide to assume crystalline form. Pool grade DE should never be used for pest control. Swimming pool DE ranges from 60% to 70% free silica!” ~Golden Harvest Organics