Dinas Powys

On Saturday I spent a morning in Dinas Powys, specifically in tetrad ST17K - the last remaining tetrad in ST17 with no bryophyte records. It proved more interesting than expected, with a fair bit of woodland in the north and some attractive limestone outcrops.

Most of the outcrops were smothered in Thamnobryum and Anomodon, but there was a small patch of Conocephalum salebrosum in one area. The best outcrop (ST149719) held Taxiphyllum wissgrillii and a fair bit of Marchesinia mackaii (the first time I've seen it in the Dinas Powys woodlands, and new for ST17). It was growing near an impressive lichen, which Sam has identified as Dermatocarpon miniatum (thanks Sam).

I finished the outing with a quick walk around Dinas Powys Common, which added some open ground species including Microbryum davellianum (spores checked) on a patch of compacted soil. I haven't entered the records yet, but the tetrad list should be up to around 60 species.

Leason Wood ramble

A ramble through a short section of the north Gower Ash woods last Friday produced a few records of interest, the best of which were a small colony of Marchesinia mackaii (photos of part of the colony and the rock it is on below, this being only the second north Gower colony I've come across) and a sheep-trodden Hygrocybe calyptriformis in an open grassy area. It would be an interesting exercise to monitor the changes in composition of the field layer in these Ash-dominated woodlands as Ash-die-back takes its course.

More Marchesinia

Marchesinia mackaii has appeared on this Blog several times recently, but this colony is rather different.

Our South Wales colonies are on limestone, whereas this one covers many square metres of igneous rock at Coed Tremadog.  I visited this outstanding lichen site, near Porthmadog, yesterday morning en route to a site visit in snowy Eryri.  Other highlights included Plagiochila britannica, P. bifaria and some potential Radula lindenbergiana.  Chris Forster Brown has found Leptodon smithii and Anomodon viticulosus there, and I'm sure that many more notable species would be found if several days were spent exploring, as the rock is very base-rich in places. 

There's a distinctly lowland, south-eastern feel to the flora, with species such as Eurhynchium pumilum and Neckera complanata more frequent than in most of Eryri.  The wonderful pink fungus Phlebia radiata appears from the NBN Gateway map to be similarly south-eastern in Britain, and no other Meirionydd records are shown.

Recording in a ravine later in the morning produced new populations of Drepanolejeunea and Harpalejeunea on a slender Ash in a small waterfall mist zone, both within a SSSI with a diverse oceanic flora but no previous records of these hyperoceanic liverworts.  It is great that even well-worked Eryri can produce surprises.

Recording in Eryri is enhanced by the wonderful landscape: snow-covered Moel Hebog was especially prominent in the background yesterday.

New turlough ??

Reading Georges blog on his trip to the Alun Valley I remembered I had also come across a large area of Marchesinia mackaii (MacKays Pouncewort) on a wooded Carboniferous Limestone outcrop on the western margin of the Nedern Brook Wetland, nr Caldicot (ST 48259 89508).

Marchesinia mackaii...I think !

That in itself is perhaps not that interesting, however the site in question certainly is !

I’ll keep it short: The Nedern Brook Wetland, is quite unusual, it is for all intents and purposes a ‘turlough’, however I don’t really like using that name in Wales.  It is dry in the summer and in the winter groundwater flooding creates a lake 1.5km long and up to 2m deep (report being finalised for NRW as we speak).  As you will know this is a very rare habitat in the UK, only one site in Wales, Pant-y-llyn nr Crosshands, currently fits the description, and there are only three very small ones in Northern Ireland completing the UK habitat.

Nedern Brook Dry (with Egret in shot too!)

Nedern Brook full of water 

‘Why have I never heard of this site?’ I hear you cry….well good question, I really don’t know, and I am convinced it deserves a higher profile, if only for its hydrology.

Hydrologically the site fits the turlough description however I would love to find some of the bryos that are associated with this habitat, namely: Fontinalis antipyretica and Drepanocladus aduncus and others, across the margins where seasonal flooding occurs.  I had a trip to the site with Julian Woodman looking for water peppers but we didn’t really attack the bryos on the seasonally flooded margin.

If anyone finds themselves near Caldicot and fancies a look let me know!

Alun Valley

I had some time to kill before a site meeting in the Alun Valley yesterday, and for once it wasn't raining - perfect conditions for a bit of mossing in fact. Sam mentioned in his recent Anomodon post that the river by Old Castle Down is base rich and should be very interesting. In fact the water levels were a bit high to find any of the lower flood zone species, but the limestone stepping stones by the ford (SS908756) were carpeted in a mix of Cinclidotus fontinaloides and Dialytrichia mucronata, with a little bit of Porella platyphylla too.

Anomodon was everywhere - on walls, limestone outcrops and tree trunks both by the river and away from it. The river sometimes dries up in the summer  - it would be fascinating to walk the dry riverbed and sample some of the usually inaccessible tree trunks and boughs.

Anomodon viticulosus carpeting a riverside tree

Part of the reason for the recording session was to try and catch up with Marchesinia mackaii, which has eluded me on the limestones of the north Cardiff ridgeway. Sam discovered it at Craig Ddu in 2013 and it proved to be widespread over a fair stretch of wooded limestone crag (SS908754).

This tetrad (SS97C) should be fantastically rich for bryos - the 69 species shown on Barry's latest map reflects the limited recording done to date. I added around 10 species yesterday, the best of which were Neckera pumila on a hazel by the river and Scapania aspera on shaded limestone (SS907756). The Scapania was recorded in this hectad back in the 1970s by Roy Perry, so it's good to get a specific grid ref for it.


I also had a brief look at an unploughed arable margin on Ewenny Down. Riccia glauca was frequent and, as always with arable, I have several specimens which need closer inspection.

Radnorshire riches

A couple of years ago I stopped for a lunchtime walk on Aberedw Rocks SE of Builth Wells, and found a rock covered with Grimmia laevigata and another with abundant G. decipiens.  Both were new to the site, and they suggested that it could be a very rich area for saxicolous mosses.  Targionia hypophylla has been known there for several decades, and there is an intriguing 20th century record of Bartramia stricta from the site, which was purged at the same time as one from Pembrokeshire [so effectively that I couldn't find out where the Pembs claim was made].

Since then the site has been on my 'to do' list, and a sunny 27th April seemed ideal.  I didn't find B. stricta or any more of either Grimmia, but there were several other good species present, including Marchesinia mackaii (photo), Bartramia ithyphylla, Pohlia cruda, Frullania fragilifolia, Seligeria recurvata, Plagiochila bifaria, P punctata & P spinulosa, Porella arboris-vitae (photo) and Orthothecium intricatum.

The two rarest species were the Nationally Scarce Plagiopus oederianus (photo, with some Bartramia pomiformis for comparison), which is abundant on north-facing rock outcrops, and the Nationally Scarce Encalypta ciliata (photo), which was only present in one small area and was last recorded on the site in 1923.

Biggest surprise was a tuft of Orthotrichum rupestre (photo), which only has 3 previous Radnorshire records and remains unknown further SW in Wales.  Its very hairy calyptra, superficial stomata, upright exostome teeth and half-pliccate capsules were distinctive.

I thought that the highlight of the day was going to be a round-leaved liverwort in a flush, which clearly wasn't Odontoschisma and seemed sure to be my first ever Jamesoniella undulifolia.  To my shock and disappointment, I found under the microscope that it had violet rhizoids, making it Jungermannia hyalina very out of habitat.

Overall it was a wonderful day of mossing, and the site is clearly of SSSI quality for its bryophytes.