Alun Valley

I had some time to kill before a site meeting in the Alun Valley yesterday, and for once it wasn't raining - perfect conditions for a bit of mossing in fact. Sam mentioned in his recent Anomodon post that the river by Old Castle Down is base rich and should be very interesting. In fact the water levels were a bit high to find any of the lower flood zone species, but the limestone stepping stones by the ford (SS908756) were carpeted in a mix of Cinclidotus fontinaloides and Dialytrichia mucronata, with a little bit of Porella platyphylla too.

Anomodon was everywhere - on walls, limestone outcrops and tree trunks both by the river and away from it. The river sometimes dries up in the summer  - it would be fascinating to walk the dry riverbed and sample some of the usually inaccessible tree trunks and boughs.

Anomodon viticulosus carpeting a riverside tree

Part of the reason for the recording session was to try and catch up with Marchesinia mackaii, which has eluded me on the limestones of the north Cardiff ridgeway. Sam discovered it at Craig Ddu in 2013 and it proved to be widespread over a fair stretch of wooded limestone crag (SS908754).

This tetrad (SS97C) should be fantastically rich for bryos - the 69 species shown on Barry's latest map reflects the limited recording done to date. I added around 10 species yesterday, the best of which were Neckera pumila on a hazel by the river and Scapania aspera on shaded limestone (SS907756). The Scapania was recorded in this hectad back in the 1970s by Roy Perry, so it's good to get a specific grid ref for it.


I also had a brief look at an unploughed arable margin on Ewenny Down. Riccia glauca was frequent and, as always with arable, I have several specimens which need closer inspection.