Two individuals nesting in barn.
Found at the base if a dead ash tree. Initially thought it was a caterpillar. No picture of the prolegs which would have rule out lepidoptera. I do not think it is a caterpillar. I think it is an hymenoptera. Elm Sawfly larva look like this. They can vary in color. What caterpillar (in Ohio) has a longitudinal stripe?
I found a good picture on the web, if I can trust it. http://www.whatsthatbug.com/2011/08/04/elm-sawfly-larvae/