Spotting

Inocybe lacera appears to be a strong possibility. "Inocybe lacera can be found throughout autumn on sandy soil, especially with pine" "Other habitats include ...coastal dunes." "Cap: 1.5-4 cm; convex to conical, becoming broadly convex or broadly bell-shaped; dry; densely hairy or scaly, becoming cracked and lacerated; brown; sometimes with pale remnants of the cortina along the margin."
http://en.wikipedia.org/wiki/Inocybe_lac...
http://www.mushroomexpert.com/inocybe_la...

I'd call this a Cortinarius species. It could also be an Inocybe, but there appears to be some rusty cortina remnants on the stipe and cap margin. Taking a spore print helps a lot with identification.

Antonio, I contacted the state park where this was found and asked for their opinion on the ID. Their "mushroom guy" said it was Tawny Grisette (Amanita fulva), but I'm just not seeing that at all. What do you think?

Yeah with that info you gather,i think Psathyrella ammophila ,is now our best chance and i read this about the collour of the gils
"At a very young age they may be a pallid brown, but for most of the lifespan are dark brown, sometimes turning black"
what could explained the collour of your's,it could be in a younger stage

And now looking at the pics again, I bet that's Ammophila brevugilata right there all around the mushroom.

I found this article associating Psathyrella ammophila with Ammophila brevugilata by Lake Huron. http://www.couchichingconserv.ca/mycolog...
Maybe that is the Canada spotting? Or it could have been on US side of the lake, I don't know.
I don't live in North Carolina so I can't go back and study the mushrooms any further. Could try to contact the park service there though.
I really don't know anything about mushrooms. I've been on Project Noah only a few weeks, and I've spent probably too many hours trying to ID my finds. It's addictive! :)

Now that you brougth the id on discussion,iam also confused :-) that is perfectly normal on ideeing mushrooms :-) they change along their life and haved several collours and shapes during their evolution,so the best is to haved the mushroom in the hand,make a spore print and se a lot of images of the specie(s) possibles,what is almost of the times very time conssuming and many times frustrating,some times the more you search,more confusing is the id :-),this year,my second on searching fungi,i haved past many hour seeing photos and reading stuff and even so,in many cases i change opinion.

Ok, I think I'm confusing myself. The marram grass that the Psathyrella ammophila grows on - I thought it was only referring to the European marram grass, A. arenaria. But does it also grow on American beachgrass, A. breviligulata? Because there's plenty of that in North Carolina. And yes, I guess Canada really is "relatively near", I just wasn't thinking of it that way. :)

As for Lacrymaria velutina, mushroomexpert.com says it is "easily recognized by its dark, mottled gills," which my mushroom does not have.

So possibly dune brittlestem is correct?

Sorry,i think that you can be rigth,however,when i give you the id suggestion,it was based in what i read in wikipédia,this one haved been reported in Canada,relatively near from you,

"Psathyrella ammophila has a wide but sparse distribution throughout the European continent and in limited coastal locations outside Europe, with records of collection in Algeria, New Zealand, and Canada. "

i search furder and i think that could be also a
Lacrymaria velutina

AntónioGinjaGinja, From what I am reading, dune brittlestems are not in the United States. Also, marram grass has only been reported on the west coast. Perhaps another psathyrella?