This is Kirtland's Snkake (Clonophis kirtlandi). It is a really neat snake that is only found in small areas of the US in IN, IL, OH, and a few spots in nearby states. It is an endangered species over most of its range. You are lucky to have such a unique and rare critter in your yard. I hope you will protect them. Although....if you didn't know what it was, why were you handling it? This post was edited by FHFchrish on Fri, Sep 5, 14 at 9:25

An identification key ... the squarish blotches on the back don't connect with the squarish blotches on the sides. It's a sort of "chequerboard" pattern. Nasty bite if you manage to catch one - not venomous, but the teeth are sharp and they bite hard - and the secretions from their anal gland they release if you catch one are incredibly vile stinky nasty stuff. (a friend's daughter managed to get bit and "slimed" when she caught a big one, planning to put it in her garden pond as a pet ... she found out the hard way it's not like catching froggies)

I assume that is a captive snake (or an escaped captive). While the pattern and coloration might first suggest that it is a striped morph California Kingsnake (Lampropeltis getula), the head shape and pattern tells a different story. The head shape looks to me like that of a milksnake (Lampropeltis triangulum). Therefore I am pretty sure this is one of the captive hybrids between a Cal King and a Milksnake.

The only venomous species up that far are the Timber Rattlesnake and Massasauga. It certainly isn't a Massasauga and it doesn't look right for the pattern of a Timber Rattlesnake. Both of those species are restricted to the very SE corner of the state and the Massasauga may be extirpated. Actually, the snake it looks most like to me based on pattern and body morph is an African Puff Adder which doesn't occur in North America. Are you 100% sure of the photo origin (i.e. did you take it)? Lots of photos get passed around the internet with dubious or deliberately changed locations.