I am currently reading a memoir about a Jewish family living in Tennessee in the 1920's. The title of the book is "The Jew Store" and it is a very enjoyable read that I would recommend to anyone. At any rate, I bring this up because I came across an idiom in the book that I had not previously heard. The idiom refers to lack of trust and basically says that when you don't trust someone - you trust them "about as much as a goat in the gladiolas." This got me to thinking about the role geography plays in idioms. In Michigan, when we don't trust a person, we say, "I trust him about as far as I can throw him."
I think it would be fun to start a list of region-specific idioms. If anyone can think of an idiom that they grew up with that is not common across the U.S. please send it to me by clicking on comment below.