These pests are mollusks, and are related to clams, oysters, and other shellfish. They feed on the leaves of a wide variety of garden plants, and may completely devour a young seedling. Ripe and unripe fruit lying on the ground may be attacked by snails and slugs. This is especially true if the fruit is shaded by the foliage, as with strawberries and unstaked tomatoes. Like other mollusks, snails and slugs need to be moist all the time. For this reason, they avoid direct sun and dry places, and hide during the day in damp places, such as under flower pots or in thick ground covers. They emerge at night or on cloudy days to feed. Slugs lay masses of white eggs encased in a slimy mass in protected places. Snails bury their eggs in the soil, also in a slimy mass. The young look like miniature versions of their parents.
Apply a bait containing metaldehyde in the areas you wish to protect. Also apply in areas where snails and slugs might be hiding, such as in dense ground covers, weedy areas, compost piles, or pot storage areas. Wet down the treated areas to encourage snail and slug activity that night. Repeat every 2 weeks as needed.