By Carol Savonen

After years of studying the effects of slug baits for the Oregon grass seed industry, Oregon State University entomologist Glenn Fisher has learned a lot about battling slugs. Only two effective chemicals are licensed and made into slug and snail baits for use on home gardens in the United States—metaldehyde and iron phosphate. He and his colleagues found that the less-toxic slug baits containing iron phosphate are as effective as metaldehyde baits for controlling the slugs that damage gardens and landscapes.

Iron phosphate slug and snail baits have been registered in the US since 1997. Products containing iron phosphate include: Sluggo, Escar-Go! and Worry Free. Iron phosphate baits have proven to be relatively non-toxic around children and pets, unlike those containing metaldehyde, according to the U.S. Environmental Protection Agency.

Metaldehyde has been an active ingredient in slug and snail baits since the 1930s. Products containing varying concentrations of metaldehyde include: Cory’s Slug and Snail Death, Deadline, and Slug-Tox. These products are sold as granules, sprays, dusts, pelleted grain or bait and are typically applied to the ground around plants or crops, to attract and kill slugs and snails.

Metaldehyde may be fatal to dogs or other pets if eaten. The death of birds feeding in metaldehyde-treated areas has been reported in the scientific literature. These deaths were from the birds eating the slug bait, not dead slugs. The four percent pelleted metaldehyde bait, a concentration commonly sold to home gardeners, is reported to be toxic to wildlife, according to the EPA.

When using baits, follow all label instructions and heed all label warnings. Don’t allow baits to contaminate the edible portions of plants.  NWGN

For more information, visit http://extension.oregonstate.edu/