Many snakes 'rattle' their tail as a threat. Just look thorugh pictures of your native snakes until you find a matching one. Long and skinny and dark = black racer?

Thanks ever so hoosierherper! 8-] ICA, Sophie ^i^

It's a Northern brown snake. Small and totally harmless.

Eastern Hognosed Snake (Heterodon platirhinos). Harmless toad-eaters. That snake looks suspiciously skinny at the posterior end of the body. Might be a female that just finished nesting. They lay eggs in burrows or hollow logs, etc. The babies are cute as all heck!