Wednesday 17 January 2018

Surprising urban wall moss


My most surprising bryo find of the winter so far has been Ptychomitrium polyphyllum growing just a stone's throw from the Butterfly Conservation Wales office in Hafod, Swansea. I first noticed a cushion of this moss growing on the sandstone coping of a sloping wall back in November, but only remembered today to take my camera along to get a few photos. I must have walked past it countless times last year before I noticed it. The moss is in the foreground of the photos below. It is close to a busy road junction and must experience pretty high levels of nitrogen pollution.

I noticed today that as well as the large fruiting cushion there is a small non-fruiting cushion nearby (on the right-hand side in the photo below left).
The associates are all mundane species: mostly Grimmia pulvinata with some Bryum capillare and a tiny amount of Tortula muralis. The rest of the wall is almost devoid of moss apart from a few scraps of G. pulvinata here and there.
I've not seen this moss in an urban situation before, but perhaps it isn't so unusual. Sam's Pembrokeshire flora mentions its persistence on imported rocks at County Hall in Haverfordwest, shwoing it can survive some pollution.


3 comments:

  1. Fascinating record George. Not quite as out of context as yours, but I saw a few tufts on slag wall by Llangennech railway station (pretty much at sea level) at the start of the month.

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  2. I have a 'pet' colony of three tufts that sit on a sandstone bridge parapet over the canal near where I live - only colony I have seen locally in the valley, although lots on the hill not too far away. Seem to recall Sam spotted some on a poplar near Ebbw Vale years ago (hope my memory not playing tricks) about the time the steel works closed - air quality must have been pretty poor then.

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  3. Yesterday I happened to walk past my 'pet'colony and found it has all gone - due to its quite inaccessible location, I can only imagine that someone climbing must have dislodge it.

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