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Horticulture and Home Pest News
Horticulture & Home Pest News is filled with articles on current horticulture, plant care, pest management, and common household pests written by Iowa State University Extension specialists in the Departments of Entomology, Horticulture and Plant Pathology.

Slugs sink their teeth into gardens

This article was published originally on 7/15/2009

There seem to be plenty of slugs in my garden, but I hope not in yours. Slugs leave small, irregular holes all over the leaves of plants. They especially seem to like my hostas but they are not picky feeders. Slugs are difficult to detect because they feed only at night. Slugs look like snails without a shell. They vary in size from less than an inch up to 2 inches in length, grayish colored, and a bit slimy to the touch. In fact as they crawl along they leave a slime trail.
 
Slugs need moisture to survive and are found under mulch, rocks, logs, and other damp locations. My hostas tend to be eaten because they grow in a garden that is shaded and holds the moisture longer.
 
Reducing slug damage is not an easy task and nothing will fix holes already there, so your first question should be – how bad is this and can I live with the damage? If you do decide to try to reduce the slug population you should combine several tactics. First, remove mulch and reduce moisture from around the base of afflicted plants as much as possible. Remove slugs you find either by using a trap such as a board on the ground that slugs will gather under or pan traps with beer as a bait. I assume cheap beer works fine and would not waste expensive beer on this. Remove dead slugs daily or it will get pretty disgusting. Finally there are commercially available slug baits available containing a molluscicide, but they are best used in the spring or fall.
 
For more information about slugs and control tactics please see this Yard & Garden Column.
 
Slug damage to a hosta leaf
Slug damage to a hosta leaf.

 Slug on a leaf with a small slime trail.
Slug on a leaf with a small slime trail.