Freaky long, fat snake skin

Zeke went balistic one day out behind the shed. I found him attacking this snake skin. It was huge, luckily though it wasn't as big as the other 5 ft skins I've found, including one by our back porch. He's been going crazy trying to dig under the shed for a while and now I know why. Before we thought it was the rat that Chase had seen months ago, but now we know there are a few snakes living there, including a big one. I'm pretty sure there might be a den there because I saw some baby snakes out there when I took some trash out. The baby snakes were garter snakes.

This skin I couldn't tell what it was, so I went online to research and from what I researched and asked friends it appears to probably be a rat snake. Garter snakes don't get this big, and are brown or black. I also found out that it's not poisonous, which was my main concern in trying to identify it. You can tell from a snake's skin if it's venimous or not by looking underneath near the anus opening I guess, not sure exactly where that might be, I didn't venture that close to find out. I took the pictures and examined it on the computer later. Anyway, if you look at the scales where they change to tiny double side by side scales then you're ok, it's not venimous, if it stays in one singular section almost like a "v" then it's venimous. I figured because it was so big it probably wasn't a copperhead, which is really the only venimous snake with that coloring it could be. I was worried though because the other night while dropping off Bailey's friend, Bailey and I got out of the car and almost stepped on a snake just sitting there in the driveway. I ran back inside for a flashlight to identify it and it had already started to slither away into the grass. I freaked out, because it looked like a copperhead. It was probably a rat snake though, it was dark and I didn't get a very good look. I've been told if we have a lot of the nonvenimous snakes around, which we do, then it's a good sign, because they actually help to keep the venimous snakes away. I HATE snakes by the way!