Maine, there is a lot if misinformation out there about IDing snakes what you were told is one of them. the north has two poisonous snakes, copperheads and rattlers. The south has both of them plus cottonmouths and coral snakes. There are several different kinds of rattlers in the US. What you should do is to either go to a place where you can look see the various species of snakes and some non poisonous ones. Once you actually see a poisonous snake you will not forget what they look like or confuse them with good snakes. More milk snakes, immature black snakes and common water snakes get killed in mistake for copperheads than you can shake a stick at. Water snakes are more aggressive than any copperhead I have ever seen. I once found myself in the middle of a whole bunch of copperheads that had just come out of a den, my cousin and I walked right into the middle of them till we saw one. As we looked around us we were surrounded. We just slowly and carefully walked out of them. Of course we were crapping bricks. The only thing about snakes I worry about is surprising one stepping over a log or rock. Then we have the nut cases who have their homes full of deadly snakes from other countries that I am not familiar with and occasionally get away.