Your best bet would probably be to contact a local horticultural or field naturalist society near you and ask them where to look.

Barb
Ontario, CANADA

I used to see Dutchmans Breeches as a kid when I lived in Shawano County. Also, saw some wintergreen and pink orchids, that we called lady slippers.
There must be a strip of acidic soil that runs somewhere in midstate, because these plants seem to grow wild in such areas. Also remember going even further north and picking blueberries several times during my youth.(the 50s)
I expect if you called your local DNR agent and asked him, he would know where you could observe and even photograph some of the lesser-known wild flowers.
I have found the DNR to be truly helpful and friendly.
Pondy

Not that this helps...but we have dutchman's britches growing in our pastureland, as well as white trilliums, Mayapples, dogtooth violets, something we called Sweet William (which appears to actually be mountain phlox?), and the most adorable bluebells. I'm attempting to cultivate some triliums (from purchased starts) in a shady spot in one of my gardens. So far I've been successful - they sprouted this spring, without blooming. I'm hopeful for some unique blooms next year.

Eventually I hope to also cultivate the bluebells and dutchman's britches in appropriate spots as well. Here's hoping.

-jaz.

Gr