Many thanks to Doug, Frogleg and everyone else for your advice. More than
I asked for and much appreciated! I'll check out that book you mentioned,
Doug.

I don't think I'll have to worry about the snails after all. After about 5
hours backbreaking work digging up the old soil and carting it off and
replacing it with new, fresh soil the snails should be gone. It's amazing
how one can underestimate things when it comes to gardening. It's just a
small plot I'm talking about--maybe 4 by 6 feet. I thought "Oh, it'll only
take an hour or so to dig the old soil and up replace it. And the 12 bags
of new soil should be plenty. Well, five hours later the 12 bags only
refilled about a third of the plot. So no tulip planting yet.

Back to the garden centre!

Once again, thanks to everyone. I only wish the people in the
alt.animals.raccoons newsgroup had been as knowledgeable when it comes to
advising me how to prevent the raccoons from digging up my new sod (chicken
wire laid over the sod did the trick).

Happy Gardening!

David in Toronto