Waun Afon revisited

 

It is always worth revisiting unusual habitats, and the largest peat bog in Gwent is certainly worth repeated visits.  I first looked at Waun Afon with Graham in the early 2000s, returned a few years later on my own, and then carried out an NVC survey of the bog over several days in ca. 2014.  Last week I looked at the heathland along the south-western edge of the bog, NVC surveying the area between the peatland and the main track along the bog's western edge.  This southern part falls in a different tetrad to the majority, so I took the opportunity to boost the total for SO20K from <50 to >100 bryophyte species.  Highlights within the heathland area were a small patch of Bazzania trilobata, two boulders with Barbilophozia attenuata, one with B. floerkei, and a rather decrepit patch of Polytrichum strictum.  A quick walk up the side of Cefn Coch to compare the heathland there with the area I had been surveying revealed increasingly abundant Rhytidiadelphus loreus and star find of the day: the first Sphagnum quinquefarium in VC35 for nearly 100 years!  After completing the survey I wandered south to the ruin of Ty Rheinallt noting Archidium alternifolium and Riccia sorocarpa on a track and some remarkably high altitude (390m aOD) Syntrichia papillosa on an Elder.  All in all, a worthwhile day.

Sphagnum quinquefarium in the Black Mountains

I have to confess I've scarcely looked at any bryophytes for a few months, but a pretty pink and green banded Sphagnum caught my eye earlier this week, while I was surveying for Welsh Clearwing moth in the Black Mountains. I hoped this might be Sphagnum russowii, but my samples have three spreading branches per fascicle - so I think this must be S. quinquefarium.

Sphagnum quinquefarium

There was an extensive patch of this moss growing in bilberry heath on a NE-facing slope above the Grwyne Fechan (SO217234). Perhaps not an unusual sight in the Brecon Beacons National Park, but it's the first time I've seen this moss away from woodland.

Sphagnum quinquefarium habitat

Sphagnum quinquefarium in Glamorgan

Sphagnum quinquefarium in the Sychryd Valley

It is odd that we don't have many records of Sphagnum quinquefarium in Glamorgan, since there are lots of steep Sessile Oak woodlands in the county that look suitable for this ancient woodland species. This site is only just in VC41, being on the Glamorgan side of the Sychryd Valley (SN91580800) and not far from where we saw it in the Mellte Valley a few weeks ago. Some plants were a striking pink colour (see photo) and stood out even for people with compromised colour vision. Nearby, some Marsupella emarginata var. emarginata on a wet, vertical, sandstone outcrop with Saccogyna viticulosa and Lejeunea cavifolia was the only other highlight.

During a quick trip up the Pyrddin Valley to Sgwd Gwladys to photograph Anoectangium aestivans and Breutelia chrysocoma, we recorded Lejeunea patens, L. lamacerina and L. cavifolia in the vicinity of the waterfall. A rotten log there had a mixture of Riccardia palmata, R. multifida and Odontoschisma denudatum. 

Anoectangium aestivans, Sgwd Gwladys

Breutelia chrysocoma, Sgwd Gwladys

Sphagnum quinquefarium (Five-ranked Bog-moss)

Sphagnum quinquefarium in Mellte Valley (Brecs)

A fascinating Sphagnum that grows in Sessile Oak woodland with species like Dicranum majus, Plagiothecium undulatum and Rhytidiadelphus loreus. It likes well drained sites, so the steep woodland in the Mellte Valley is ideal and a good place to see it is on the eastern side of the river near the old gunpowder works.There's lots of S. fimbriatum there too, but side by side the differences between these two Acutifolia Sphagnums are striking. People with 'normal' colour vision will be able to see the raspberry-pink tints in S. quinquefarium. Also the fascicle structure with 3 spreading branches is more or less unique for British Acutifolia. Up close, the straight, angular (5-ranked) structure of the branches in the vicinity of the capitulum, is obvious.

Capitula and branches of Sphagnum quinquefarium (Mellte Valley)

I think I'm right in saying that the only (well) known population of S. quinquefarium in Glamorgan is in the steep oak woodland on the Glamorgan side of the River Pyrddin, near Scwd Gwladys. There must be other suitable sites elsewhere in the county, so it's worth keeping an eye open for it.