Rosebush Quarry and Craig y Cwm

The old slate quarries at Rosebush

Sam described the Rosebush Quarries as the best non-designated site for bryophytes in Pembrokeshire. I'd never looked at it, as it's been often-covered in the past, particularly by Martha Newton on her FSC courses. But Cotoneaster survey and a sunny day after rain gave me the excuse to do have a poke about. 

I added Bryoerythrophyllum ferruginascens to the site list in the car-park by the old quarry buildings. Unknown in Pembrokeshire until recently, this is now no longer a county rarity.

Several patches of Pohlia elongata in the south-eastern quarry pit were also new, and a second record for the county. Potentially more interesting was a Cynodontium growing on a ledge at the base of a worked face near one of the tunnels. With bistratose margins and more or less smooth cells it keys to C. tenellum which looks as if it might be new to Wales. NB, subsequently confirmed by Sharon Pilkington as new to Wales, and a long way south of previous Scottish records.

Cynodontium tenellum

I relocated some other species of interest, including Schistostega pinnata in a tunnel (with a hibernating horseshoe bat), Dicranella subulata, Grimmia donniana and Nardia compressa, the latter in a wet section of worked face. I didn't manage to find the Coscinodon cribrosus or Marsupella sprucei. With regards to the target non-native plant, the Cotoneaster integrifolius forms thick patches in several places, but hasn't yet taken over the whole quarry. Give it time...

Goblin Gold, Schistostega pinnata

Carrying on into the adjoining conifer plantations at Pantmaenog, it didn't take me long to find Campylopus subulatus on the tracks. Although there are only two other county records, it was abundant along at least a kilometre of track here - it must surely be widespread in other similar plantations, where it may have been overlooked. Alongside it in one location was a small amount of Ditrichum pusillum, which suggests that this too may not be quite the rarity that it has been in west Wales.  Pohlia drummondii was amongst the P. annontina here as well, in a scene reminiscent of my recent survey in Brechfa Forest.

Track with Campylopus subulatus, Ditrichum pusillum and Pohlia drummondii

I had just enough time to head out to Craig y Cwm, an old quarry on the hill nearby. This is the only known county location for Anomobryum julaceum, Solenostoma obovatum and Marsupella emarginata var. aquatica, all of which were refound. Nardia compressa is still flourishing here too. Some slender shoots of Lepidozia growing through Dicranum majus, with deeply divided lobes and male inflorescences terminal on long lateral branches, were confirmed by Nick Hodgetts as L. pearsonii. This hadn't been picked up in Pembs before, and the habitat is typical - apparently it likes the Dicranum. One other good find here, subsequently confirmed by Sharon Pilkington, was the second Welsh record of Thamnobryum maderense. Despite having obviously complanate shoots compared to T. alopecurum, it is sometimes considered a worthless taxa, but this specimen confirmed with the published characters on leaf shape, cell size and shape, and nerve cross section.

Anomobryum julaceum

Thamnobryum maderense nerve section and mid leaf cells

 

Waterfall Walk

A fine day, not too warm, and with a few hours available led me to visit a site I’d not been to before in spite of it being only a few miles away from my home as the kite flies.  Arthur had told me it was worth getting to and he had visited it with Sam in May 2004 so I knew what I was likely to see and there was one particular moss I was interested in refinding.

The walk starts from the now-derelict Dyffryn Castell on the main road and heads SE through the farm at the foot of the hill.  Then a slog up the track before branching off on a tiny footpath across the moorland until one of the lakes called Llynnoedd Ieuan  is reached:

This lake itself has so far proved unremarkable bryologically, as a previous visit with Tim Rayner had shown, but there are another two lakes to explore another day.  

Pressing on across the moorland, the land suddenly drops away and the small stream drops over the edge in a spectacular waterfall.

By dropping down through the forestry and then working back up the stream, it’s not too difficult to reach the bottom of the falls.  Most of the rock is clearly acidic and, although it’s possible to work up the edge of the series of cascades that make up the waterfall (unlikely as it looks on the photo), the bryophytes tend to be very common things like Scapania and Marsupella. It's not a very big stream and may well dry up completely on occasion and it also faces south.  But there are a few pockets of strongly calcareous rock at the bottom which are easily detected by the presence of huge cushions of Tortella tortuosa with a few patches of Pohlia cruda.

 

Then at the bottom of a few of these rocks are cavities where the delightful Isopterygiopsis pulchella grows, a plant I’d not previously seen in the county.  A few setae are visible in the photo for this is a monoicous moss, unlike some of its look-alikes.

 Associated bryophytes here were all common things like Heterocladium flaccidum and Mnium hornum, all carefully checked of course.

 

 

I didn’t have time to thoroughly explore the site but I managed to add a few more mosses and liverworts to Sam’s extensive list and then it was back across the moorland with a few Wheatears for company.

 Brechfa Forest

I picked up a job in Brechfa Forest on Wednesday, monitoring some translocation work which had been undertaken in association with the wind-farm. Populations of Pohlia drummondii and Campylopus subulatus had been moved when new tracks had been constructed a few years ago, and distributed along two unsurfaced tracks. Both had quickly dwindled as vegetation cover increased, and the Pohlia had disappeared from both receptor sites by 2019. It persists on one of the two ditch-side locations found in 2019, although it appears to be much less frequent than it was then, and less abundant than the Pohlia bulbifera alongside. 

The Campylopus hangs on in small quantity on one of the receptor sites - a damp, shaded track, where it struggles alongside Sphagnum denticulatum, S. cuspidatum and Polytrichum commune. I found a few plants of Atrichum crispum in one of the few more open patches here. 

Atrichum crispum

Perhaps unsurprisingly, given its abundance on forestry tracks further north, a deviation from the monitoring spec revealed Campylopus subulatus to be abundant and sometimes dominant on various sections of secondary track, which are still surfaced with local shale and more acidic than the new limestone ones as a result. Tom tells me that there may be cryptic species within a subulatus aggregate, and Ceredigion specimens are amongst those being sequenced at the moment. Still no Bryoerythrophyllum campylocarpum to be found with it, but there was some B. ferruginascens (including an all green form which had caused us both confusion when I first collected it from a site near Aberystwyth last month). Some fruiting Weissia rutilans in a few places as well, which may or may not still be locally rare.

Typical Campylopus subulatus track