Not a maidenhair, perhaps something in the Dryopteris genus such as Dryopteris arguta.

Note how the pinna are shorter at the base ... that would be a characteristic to look for when trying to identify id. I can't find enough pictures of Dryopteris arguta to see if it always has that trait.

On the eastern half of the US, we have a fern called Thelypteris noveboracensis (New York fern) that always has that trait.

Possibly Dryopteris filix-mas (Male Fern), a native of the interior of your state.

Here is a link that might be useful: Dryopteris filix-mas

Thanks! I looked all the suggestions up and so far Dryopteris arguta comes the closest. I have a Dryopteris filix-mas, and it doesnt really resemble the one in the pic. Unlike the Male Fern, this fern doesnt have those brown furry scales at the stems. The stems of this one are, tward the base, a mahogony sort of color. And, I dont know if this helps, but the unknown fern was unfurling new fronds through out the summer. I cant really coment on its habit, since it was barely more than a seedling. I can post more pics of it in the spring (if it makes it through the winter)if you think that would help.
CMK