Help with Snail Problem
About 3 years ago I started to notice a snail or two either in one of my planters out front or sticking to the siding on my house. I don't think I'd ever seen one before here in Tigard until recently, or in the other towns I've lived in here in the Willamette Valley: Wilsonville and Canby. I buy my flowering plants from local nurseries, so I'm guessing that's where the snails came from. Now of course there are more, big and small and I am wondering if this is a relatively new invasive species in this area, and if I should try to eradicate them the same ways I go after slugs. Help please! Thank you. Ruth Bollen
Washington County Oregon
Thank you for your question about snails, Ruth. I'm not sure how much you want to know about snails, but there 14 pages of them, with pictures and descriptions, in this ODA publication. The brown garden snail described there on page 32, as well as the commercial escargot snail, has recently been described as "the greatest risk to nurseries given its status as a quarantine pest and its establishment in sites around Oregon and Washington" in this OSU article. That may be what you have, but many varieties are native and you may have missed seeing them.
Although written primarily for commercial nurseries, this latter article notes in its control options that many slug chemicals (iron phosphate--Sluggo--being organic) are also effective on snails, and available to home gardeners. Just be mindful of the ones that are also toxic to pets. If you choose chemical method control, please follow all label directions for use.
I hope this information is helpful. Good luck!