Slugs feed on a wide variety of plants including flowers (annuals and perennials), vegetables and ground covers. They are especially fond of hostas. They can devour seedlings completely and cause large holes or tattered edges on larger leaves. Damage occurs at night as these organisms are nocturnal and hide during the day.
A number of strategies can be used for control. Handpicking can be effective but is most effective if done after dark with a flashlight. Alternatively, rolled newspapers or boards placed near where slugs are feeding will serve as a hiding place for slugs during the day. Check the traps in the morning and destroy any that are found. Placing slugs in a jar with soapy water will kill them. Other, more entertaining methods of control can be used such as stomping on them, placing them on concrete and running them over with a vehicle or bicycle or even sprinkling them with salt to draw water out of the slug, leading to its’ demise.
Baits can also be used. Gardeners have found that a pie tin, buried to the rim and filled with beer will attract and kill slugs as they crawl in and either cannot or will not crawl out. Commercial baits are also available with the most common active ingredients being metaldehyde and iron phosphate. Products with metaldehyde can be toxic to cats and dogs if ingested in large quantities so place this product in spots the slugs can reach but pets cannot. Iron phosphate is safe for pets and also does a good job of killing slugs though it may take 3 to 6 days to work. (Ward Upham)