Snails and slugs are not insects, though some gardeners might think of them as such. They are, in fact mollusks. Signs of infestation include the appearance of large, ragged holes in low-growing plants such as strawberries, hostas and lettuce. While preventive maintenance is best for both snails and slugs, iron phosphate-based slug and snail bait is effective for controlling infestations after they occur and is less toxic to children and animals than baits which are metaldehyde-based. Use copper flashing to keep slugs and snails off of tall plants or trees.
Remove all the slugs and snails which you find on the plants in your garden. Place them in a plastic container and put them in a place where birds regularly feed if you wish. Otherwise, they can be killed using salt or beer.
Place the iron-phosphate based slug and snail bait around the plants in your garden. They are non-toxic to household pets, birds and people, so you don't have to worry about covering them up.
Unroll the copper flashing and press it into the ground at the base of the plant that you want to protect. To protect trees from snail and slug infestation, wrap copper wire around the base of the tree to prevent them from climbing up to the leaves of the tree.
Dig a hole in your garden deep enough to hold the plastic container. Place the container in the ground and fill with 1 inch of inexpensive beer. The snails and slugs will be attracted to the beer, fall into the liquid and drown.