Rhodobryum roseum at Kenfig

During a Glamorgan Fungus Group meeting on Saturday I came across a pretty big patch of Rhodobryum roseum in dune grassland at Kenfig NNR.  There were several hundred rosettes within about 2 square metres (far more than I've ever seen before) so I thought it was definitely worth a pause from the fungi to note the grid reference (SS7885681600) in case it's a new patch.

Old Acquaintance

Travelling over Mynydd Llangynidr last week I made a quick roadside stop to see if I could refind Rhodobryum roseum at the site where I encountered it for the first time many years ago whilst recording some quadrat data in good grassland fungi habitat.    Sure enough it was still present – none of the plants was particularly crowded with leaves and so no chance of stringing R. ontariense, which is known from several European countries (Sweden, Finland, France Spain etc).  I am not entirely sure if there are strict habitat preferences between the two species, but R. ontariense may be more of a lowland species.   It is a very long shot, but it is worth bearing ontariense in mind if you ever come across Rhodobryum (differences are mainly number of leaves, leaf shape, extent of recurved margin and costa section – the following link takes you to a pdf of a paper that is probably still valid.... https://helda.helsinki.fi/bitstream/handle/10138/36724/299944_096_1972.pdf?sequence=1

If you search Rhodobryum roseum pics in Google a lot of those originating from America may well be ontariense.

Most Rhodobryum I have seen in the BBNP (Brecks and Mons) has been on high ground (but this may be because this is where the limestone usually outcrops) either in secondary calcareous grassland on old quarry spoil heaps or around natural limestone outcrops and pavement.  I did once show Rhodobryum to a non-bryologist colleague who the very next week came across some in a patch of semi-improved grassland over Old Red Sandstone in the Black Mountains north of Abergavenny! (and it seems Sam and I also recorded it on the ORS above Crickhowell some years ago – of which I only have a very very vague memory-  a bit like a dream).   It should be present on Morlais Hill if you haven’t had it there already.  

A couple of old pics to illustrate this lovely moss. 

Rose-moss at Cwm Ivy Tor

When heading back after a bird count at Whiteford today I decided to take a quick look at the Rhodobryum roseum site at the base of Cwm Ivy Tor, where Veronica Shenston and myself first recorded it in 2011. Buoyed by the frequency of shoots in this area I thought I'd see how far up the tor the population extended. This small colony appeared to peter out fairly quickly as I headed up the slope, but just below the top of the tor it occurred abundantly on many of the grassy ledges shown in the photo above, even making up a significant part of the sward in places (photo below right is a close up of the area shown by the red penknife above SS4350594041). I was running late so I did not attempt an estimate, but there were possibly thousands of shoots along a 25m section of the ledge I walked.

North-west Gower is a bit of a hot spot for this species as Peter also found two sites at St Madoc's Christian Youth Camp in 2008 and 2009. All sites comprise well-drained, sandy soils around Limestone outcrops and are rabbit/sheep-grazed. The sites at Brandy Cove and Kenfig found by Sam now make it four post-2000 tetrads for Glamorgan.

Plenty of other interesting species and as always a few samples to check, but Porella platyphylla was very abundant on the outcrops with frequent Reboulia hemisphaerica on soil gaps.

Also on the walk back past the dune slack I saw a few good candidate Bryum warneum capsules and where the yellow dunes started there were some patches of Pleurochaete squarrosa growing amongst a carpet of Tortella flavovirens & Hypnum cupressiforme var. lacunosum. P. squarrosa is a good candidate for discovery in NPT Charles.