If you don't have ducks, or if your slug plague is too vast, you could get some of this stuff: http://www.pestproducts.com/sluggo.htm I have used it in the past, against our plague of snails in California, and was pleased with the results. You could also gather the neighbour kids - I offered the kids 1 cent a snail, and got rid of almost 10 dollars that weekend! (The kids were at the age when they still "played by the rules", and I don't think I was cheated by much ) I had several years of almost snail-less gardening after that one weekend.