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Why can salt be used as a weed killer?
Salt is an excellent weed killer - it's also excellent for killing just about anything that grows. Not only will it kill your weeds, but it will kill your grass, your flowers, or anything else you put enough of it on. Salt can be used as a preservative for meats because it kills bacteria. It will kill animals if they eat too much of it and will kill fish if there's too much if it in the water. The reason for this is that salt is a natural dessicant - this means that it dries things out. The salt pulls moisture out of the cells of the plant, the bacteria, the animal, or the fish, leaving the organism too dehydrated to survive. This doesn't mean that you can't eat a little salt on your favorite foods - just don't be surprised when it makes you thirsty!
(published on 10/22/2007)
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