Bitterly cold and strong winds.
Here's what I've worked out so far for Polytrichum formosum.
This shot shows the general plant form with mature spore capsules.
And this is a close-up of the side view of a capsule - now empty.
Capsule is about 8mm. from left to right.
I hope at some point to be able to photograph the capsule with its opercule in place. The opercule is a 'flap' or covering that opens when the weather is right, so that the spores have a better chance of dispersal.
The white rim to the opening is actually 64 teeth. Good binary number.
The pale yellow spikes here are partially formed (young) sporing growths (sporophytes), which are parasitic on the growth of the previous generation. The darker growth leaning towards the upper right is the male parent - the antheridia.
This is a close-up of the immature sporophyte.
The pale yellow component is about 15mm tall.