Here in the wet, relative cool Norhwest of the USA, we have a number of imported slugs, and one native one. The native one (the banana slug) is well behaved and stays in the woods; the others are a scourge. What I've used for the past several years, with great success, is a commercial product that has iron phosphate as the active ingredient. Sluggo is the brand name available in our area; there are a.number of other brands. I start to apply the material in late winter, before the slug eggs have hatched. It does dissolve into the soil, but this takes a week or so, and remains effective until completely gone. I renew the material until warm weather arrives, and all the slugs have hatched, eaten a bit of Sluggo and gone off to that salad bowl in the sky. The summer and fall are mostly slug free, with a problem only with the odd slug that slimes its way in from the woods. During this time, I keep some of the material around the periphery of the beds. In the fall, I again treat the whole beds, in the hopes of offing any slugs present before they can lay eggs. This regime works well, and causes no environmental problems (manufactures' claims and personal observation). I'd keep the material out of the reach of chickens, but wild birds and animals appear to be smarter, and don't ingest it, even when in the same location as spilled bird seed. Hopefully helpful, Dave B, Tumwater, Washington, 7A (currently at the nozzle end of a "pineapple express")