View the spoiler for my guess at what I think it might be, but please first come to your own conclusion before looking at mine — I don't want to bias your guess.
My guess
Psilocybe cyanescens
They were found in mid-november in the Salish Coast region of Cascadia. They were growing out of woodchips composed of a mixture of western hemlock (majority), and western red cedar.
Side view of one full mature specimen:
A group with a sample of the substrate (the cap appears to be umbonate):
A closeup side view, and internal view of the stem (it appears to be hollow):
Cross section of the gills — they appear to be adnate, or sub-decurrent:
Underside of view of the gills:
Spore print (first on white background (the split is due to two halves), second on a black background):
Examples specimens once dried:
Examples of the colony, and the location/substrate in which it was growing:
Cross-posts:
I forget the species name now, it launches its spores and you can put it up to your ear and hear the popping sounds.
Neat! Let me know if you remember it 😊