Hi shana. I find black every year here in St. Charles in a few spots. Mostly flat land that is in a mossy decaying viney tree limb type of area completely shaded with a canopy of trees. I never find them on bluffs or higher up where I find the yellows, always lower areas. Sometimes at the base of bluffs where the land starts to level off.
May not have been much help, but I do find them every year here. The forecast calls for 50+ night time temps for the next 4 days. I'm stoked!

I'll post pics of my first black find when it comes.