A bluish gray Lobaria? Margins have bluish soralia.
Scharnof talks about a L. hallii but in northern Cal. Not sure if this is just a very dry L. pulmonaria or...
On forest floor.
Lots of Lobaria pulmonaria (Lungwort) had fallen from upper branches onto the ground. Lungwort has nitrogen, which fertilizes the soil in the forest.
I wish I could've actually seen the face I made when I first saw this. Probably the coolest lichen species I've ever seen--though, sadly, I fear many other people think so too, and some are less kind: I saw several tree trunks with disturbed patches of mosses where it appeared someone had removed a portion of the moss, or more likely, this funky-looking lichen. It has a quality about it that just makes you unthinkingly reach out to touch it.
Uncommon; on moss-covered tree trunks in beech-maple-hemlock forest along Tahquamenon River.
Lobaria is a genus of lichens commonly known as "lungwort" or "lung moss" as their physical shape somewhat resembles a lung. Lobaria species are unusual in that they have a three-part symbiosis, containing a fungus, an alga and a cyanobacterium, the presence of the cyanobacterium allowing nitrogen fixation.