I ran across this snake a few weeks ago, I think its a cotton mouth, but not for sure. What is it?

UGH, break out the WAKI!

Your last photo looks like the one in this picture of the Florida Cottonmouth, particularly with the diamond "bullseye" pattern. From what I read I sure hope you were using a telephoto lens to snap those pictures! I don't have any personal experience with them but I wouldn't be chasing it. (I chased a Bull Shark once on a dive in the Caymans to get a good photo and didn't learn until afterwards that it's one of the more aggressive varieties. Never did it again.)

Something that I would run from! <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />

Looks like a Water Moccasin to me... Keep your animals and kids away from that thing. Their posion can really do havic on flesh.

He was probably 5 feet away from me, but he didn't want anything to do with me and went into the woods. It wasn't aggressive at all. I've seen cottonmouths that were much darker and solid color. I read there were many different types though.

It is a younger cottonmouth, (water moccasin), formal name = Agkistrodon piscivorus. The young ones have very distinctive banding and patterns. As they get older the patterns start to fade and the overall look becomes more dark or "muddy". They can get VERY pissy at times.

Dangerous. <img src="/ubbthreads/images/graemlins/wink.gif" alt="" />

I leave the non-venomous ones alone but I'd have to whack that one with the Tramontina if I had it handy. I have had moccasins chase after me on a few occasions. They can be more aggressive than most snakes. Most of the time, they will flee, though.

Moccasins are the most aggressive snakes I've ever encountered. Not all of them, but they are the only ones that have actually advanced on me.

Man, you are lucky that SOB did not turn and take a few strikes at you. That cottonmouth would have been dead if it were me.

+1 grew up with them, they usually leave you alone