Friday, 16 December 2016

Cwm Dulais (Pontarddulais)

This afternoon I spent 40 mins of Alfie-time looking at a small part of what is a much wider area of south-facing coal spoil in Cwm Dulais SN613036 - how many Cwm Dulais's must there be in Wales! An unremarkable total of 31 bryos were recorded, along with what I'm suspecting must be Galium parisiense, which was locally frequent. I'm not sure if G. parisiense has been recorded on coal spoil before, but it's clearly well adapted to it and would be worth checking for on other tips. Bryologiocally, there was nothing of great note, but it was an interesting assemblage all the same, with frequent Archidium alternifolium (photo 3), Homalothecium lutescens, Hypnum cupressiforme var. lacunosum (photos 3-4) and occasional Calliergonella lindbergii, Didymodon ferrugineus, Syntrichia ruralis var. ruraliformis (photo 4) & Trichostomum crispulum. Nearby, Fontinalis antipyretica and F. squamosa were noted growing side-by-side in the river.


  1. An inventory of South Wales' coal tip species (vascular plants, bryophytes, lichens and fungi) would be worthwhile.
    Galium parisiense is definitely spreading in VC 41. With this record we now have 4 well separated sites. It seems to like well drained, slightly calcareous substrates. The reluctance to view this species as nothing more than a neophyte in Glamorgan is puzzling. It clearly has the ability to disperse itself over long distances, so why can't this be a native expanding its range?
    The occurrence of calcicoles on coal tips has always fascinated me, e.g. D. ferrugineus, Tortella tortuosa, Trichostomum crispulum, Carlina vulgaris, to name just a few. Something interesting going on with mineral chemistry there.

  2. Many tips are dominated by calcifuge species, but some sites, like this one, can have quite intricate mosaics with calcicoles well represented. I have seen a list produced by Sam of spoil species, which would be great to add to. I could add a tab to set up a little project.