I have used a lot of iron phosphate over the past several years to control white snails & slugs and it didn't seem to have any impact on the earthworm population at all; they're everywhere when I dig or move pots.

I had a bad infestation of white snails and now I don't any more.

http://entnemdept.ufl.edu/creatures/misc/white_garden_snail.htm

Thank you so much, Carol. I'd much rather use something natural.

These are 2 brands I used:

I use beer, i take a Dixie cup and bury it with the top just barely above the soil then fill half way up with cheep beer. The smell attracts them and when they fall in the drown. Works ok.

Glenn, like I said, tried that, didn't work. These are AA slugs, evidently. LOL

My solution is not natural at all, but it works literally overnight. Ammonium sulfate is a cheap fertilizer available at all garden stores. It looks like rock salt and, as far as snails and slugs are concerned, it works like rock salt. As soon as they try to move and hit that salt, they foam up and die. We used to have snails and slugs in the ivy, but one application of AS and they were gone, again, overnight. 25 years later we still had no snails/slugs.

None alcoholic slugs,lol,

I do know something that works well. Epsom salt,large crystal. And doesn't hurt plants

Hmmm...I hadn't thought about epsom salts, but it's good for plants in small doses, so maybe that would work if I put it on the edges near the concrete. It is a salt, after all, and salt definitely kills slugs. I had also heard about diatomatceous earth, and putting sharp gravel up next to the concrete, because it cuts their undersides and dehydrates them.