Slugs are a group of loosely related gastropods that are similar to snails, but have no shell or very small shell. There are many different species of slugs, including some that live in marine environments (sea slugs). Some species of slugs are sometimes considered to be a garden pest because they eat fruits and vegetables as well as foliage, which can kill plants. Gardeners use various methods to kill or deter slugs from their gardens. One way to kill slugs is to use salt. Read on if you want to know why salt kills slugs.
Why does salt kill slugs?
The body of a slug is made mostly of water, which is protected with body mucus. The reason that salt kills slugs comes down to a biological process called osmosis. This process causes water to move from an region where there is more water into a region where there is less water, and vice versa. The cell membranes of a slug are very porous and when salt is poured on a slug the high concentration of salt on the outside causes the water to move from the inside of the slug to the outside. Basically, the liquids inside the slug are used to dilute the salt and preserve the mucus layer. This loss of liquids caused by the salt eventually dehydrates the slug and this is what kills the slug. Although some gardeners use this method to kill slugs, it is not commonly used in agriculture because salt is harmful to the crops.