WSU Extension


Lettuce : Slugs
(revision date: 3/10/2017)

Slugs are common garden pests in western Washington. They resemble snails, but lack shells. They may vary from as little as 1/4" up to several inches in length, depending on age and species. Slugs often leave behind a characteristic slime trail, which appears silvery when it dries. Slugs typically feed at night and do more damage during cool, moist weather. Seedlings and small plants may be completely eaten, while larger plants may show only holes in the leaves.
Management Options

Non-Chemical Management
  • Clean up weeds and debris which may provide shelter. Cut tall weeds and grasses around the garden and clean up rocks, boards, and other shelters.
  • Encourage predators such as birds, garter snakes, frogs, ducks, and predacious ground beetles. Avoid use of broad-spectrum insecticides which kill beneficial insects.
  • Hand-pick and kill slugs when noticed.
  • Use chemical baits with caution, as pets can be poisoned. Iron phosphate-based baits are safer for pets!
Select non-chemical management options as your first choice!

Chemical Management

Apply bait in evening or at night as these pests feed mainly at night. Be careful not to expose baits to pets or other animals.

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.
  • Escar-Go! Slug & Snail Bait
    Active ingredient: iron phosphate  |  EPA reg no: 67702-3-56872
  • Lilly Miller Slug & Snail Bait
    Active ingredient: metaldehyde  |  EPA reg no: 8119-11-33116
  • Monterey Sluggo [Organic]
    Active ingredient: iron phosphate  |  EPA reg no: 67702-3-54705
  • This list may not include all products registered for this use.
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Caption: Slug damage and slime
Photo by: R.S. Byther
Caption: Brown slug
Photo by: C.R. Foss
Caption: Slug
Photo by: C.R. Foss