Rhytidiadelphus triquetrus further afield

The distribution of Rhytidiadelphus triquetrus in Glamorgan is partly elucidated by examination of maps from three other pretty well-recorded S Wales VCs. 

It has a very inland distribution in Pembs, largely avoiding the coast (except for a handful of very sheltered lane banks or churchyards, perhaps introduced with wreaths in the latter).

Colonies are widespread in Carms except around Llanelli and Carmarthen.  The strongest populations are on lane banks in the northern half of the county from Clunderwen to Llandovery.

Finally in Monmouthshire it is scarce except in the Black Mountains, with a few lane bank colonies around the Trellech plateau.

The first Atlas said that pollution had caused declines in Rhytidiadelphus triquetrus, and that would seem to make a lot of sense judging by its distribution in south Wales.  Roll on the time we can publish a S Wales tetrad Flora to really display these patterns!!