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:
Yeah, I would've liked to have provided a microscopic image of the spores, but I don't currently have access to a microscope of sufficient magnification to image them. Though I likely will soon, and, if possible, I will update with that information.