Grotting in the Garw

Blaengarw

It is clear from George's spreadsheet of records counts for VC41 that there are lots of tetrads in remote places which need some attention. Much of the Garw Valley in Bridgend county falls into that category. I like these old villages, which have 'paid the price of coal' (Mark Knopfler), and the way they are almost reinventing themselves as they recover from their mining legacy. 

But they are hard work! Nevertheless, on a nice day, like yesterday, you can take an easy, if long walk from the Bwlch (above Abergwynfi, in NPT) along the new, limestone-gravelled road that gives access to the Llynfi-Afan Wind Farm, which is what we did. The road also gives access to parts of SS99B (formally 15 records), SS89X (39) and SS89W (13).

Funaria hygrometrica is plentiful in the gravel and bare peat along the road, often with other common pioneers such as Ceratodon purpureus and Bryum dichotomum, but many of the calcicoles that one might expect such as Trichostomum crispulum and Ctenidium molluscum, which are so abundant along forest roads, are not here yet. The surrounding moorland is heavily grazed and unexciting but some of the peaty tracks have lots of Lophocolea bispinosa.

From Blaengarw there are a number of forest tracks which ascend through Scots Pine and finally into Sitka. There was more L. bispinosa here and lots of Calliergonella lindbergii along the roads, but there is lots more to do.

Calliergonella lindbergii

After all this the tetrad totals are still modest; SS89W = 43; SS89X = 60; SS99B = 45 and SS99C = 60; but the Garw will look a bit darker on the next tetrad map. There are also some exposed rock (Darren Goch) and gully habitats above Blaengarw in SS99B which were not accessible to us on the day and we (or anybody else) may try to get to them in the future. 

North-facing gulley above Blaengarw

A frosty day at Llantrisant Common

On 28th December I spent a sunny day recording bryophytes on Llantrisant Common with Karen Wilkinson and Caroline O'Rourke.

Although the weather was beautiful the ground frost never cleared - Karen was reduced to ripping up chunks of frozen Sphagnum to take home to identify. We probably missed some smaller species as a result - there was no chance of picking through Sphagnum in the field to look for small liverworts, for example.

We covered the western bits of the common and succeeded in upping tetrad ST08M from 46 to 75 taxa. The existing site list was largely made up of records from CCW vegetation surveys in the 90s, topped up with a few grots I recorded in 2015. There were no epiphytes on the list however, and these made up the bulk of the additions. We'd hoped to re-find Scapania paludicola, recorded in several places by CCW, and got excited by some promising Scapania in M15 wet heath, but this proved on closer inspection to be S. irrigua.

The highlight of the day was a small patch of Atrichum crispum close to a stream (5th Glamorgan tetrad, top photos below). Other finds included Calliergonella lindbergii (below left) among short grass in several places, Pseudephemerum nitidum and vegetative Physcomitrium pyriforme (hopefully safe to record) rubbing shoulders in a rushy ditch (below right) and Orthotrichum stramineum on an old willow.

 

Karen recorded 6 species of Sphagnum including S. fimbriatum and S. fallax new for the site, as well as some beautiful wine-red S. capillifolium.

We strayed into the southern part of the common, which falls within ST08L, and took the total for that tetrad from 53 to 63 taxa. We didn't have time to explore the extensive eastern side of the common and are planning a return visit sometime...

Cwm Colliery

Yesterday afternoon Karen Wilkinson and I spent a few hours looking at the bryophytes of Cwm Colliery, near Beddau. It's a big place and we only really scratched the surface, but we managed to add quite a few species for the under-recorded tetrads ST08S and ST08T.

Liam Olds has done a lot of invert surveys at this site, and had mentioned the presence of tufaceous springs - something I'd not seen on colliery spoil. We looked at a couple of these on the western side of the tip - they certainly look odd but we failed to find any unusual bryophyte species: only Didymodon tophaceus, Aneura pinguis, Cratoneuron filicinum and Bryum pseudotriquetrum were recorded on the tufa.

 

Elsewhere, we found a couple of patches of what looks like it might be Lophocolea semiteres growing on spoil under young birch - photos below. I'm not absolutely sure it's not L. heterophylla - some of the leaf tips are retuse but most are entire, and none are very notched. Photos below.

Most of the spoil was fairly species-poor but we did find small patches of Calliergonella lindbergii (photo below), Archidium alternifolium, Campyliadelphus chrysophyllus and Weissia brachycarpa var obliqua. The young willow and birch woodland was quite rich, with Rhytidiadelphus triquetrus and a good range of epiphytes.

There are large areas in the north and east of the site left to explore, so further visits are needed.

Onllwyn Coal Tips

 A few days ago, in dismal conditions, H and I spent an hour strolling around an area of reclaimed coal tip in Onllwyn (Dulais Valley). Coal tips often support ecological mosaics of calcifuge and calcicole plants and their physical and mineral characteristics are interesting. The Onllwyn bryophyte community was remarkable for its large proportion of base-loving species; e.g. Calliergonella lindbergii, Campyliadelphus chrysophyllus, Ctenidium molluscum, Didymodon ferrugineus, Ditrichum gracile, Encalypta streptocarpa, Fissidens adianthoides, Tortella tortuosa, Trichostomum crispulum. We also noted a nice patch of Climacium dendroides.

Calliergonella lindbergii

Campyliadelphus chrysophyllus

Climacium dendroides

We usually pick up Campyliadelphus chrysophyllus as scattered individuals along tracks (often associated with Didymodon ferrugineus), but here it was present in fairly dense patches. In fact, at first I wasn't sure whether it was Campyliadelphus or small Campylium protensum. The costa in Campyliadelphus leaves is really difficult (for me) to see in the field, but later microscopic observation confirmed it.
The steep, wooded side to the coal tip had a more eclectic, luxuriant pleurocarp mixture with Eurhynchium striatum, Hylocomium splendens, Loeskyobryum brevirostre, Pseudoscleropodium purum, Rhytiydiadelphus loreus and R. triquetrus, a fairly typical community for wood and scrub on reclaimed coal tips in NPT.
Coal tips are nitrogen deficient habitat. Their ecological remediation and reclamation often involves planting nitrogen-fixing  trees, shrubs and herbaceous species in order to enrich the soil with combined nitrogen, e.g. legumes such as clovers and Sainfoin and non-legumes like Alders and Sea Buckthorn. In the last few years research into the nitrogen input dynamics of northern boreal forests (also fairly nitrogen deficient ecosystems) has revealed fascinating associations between moss species such as Pleurozium schreberi and Hylocomium splendens and free-living cyanobacteria (e.g. Nostoc) in loose 'symbiotic' nitrogen-fixing relationships. In these relationships the N-fixing cyanobacteria do not appear to integrate themselves into the tissues of these mosses in the same way as they do in the cavities found in certain liverworts (e.g. Blasia pusilla) and hornworts (e.g. Anthoceros agrestis). The reason I mention this is because some of our moss collections from Onllwyn had significant amounts of free-living colonial cyanobacteria (probably Nostoc spp.) associated with them (see photo below of colony found intermingled with Ceratodon purpureus).

Filamentous cyanobacterial colony associated with Ceratodon purpureus

The colony in the photo contains lots of heterocysts, (the larger, colourless cells in the filaments), which is where N-fixation takes place in the colony. I'm sure that most of you have observed cyanobacterial colonies like this among your collections from time to time, so I thought that it might be of interest if we occasionally note species and habitats where such associations occur in South Wales. Other nitrogen deficient habitats where you might observe this are heathland (e.g among Pleurozium and Hylocomium), bogs (among Sphagnum spp.), tarmac, and perhaps epiphytic habitats.

To put this into perpesctive, the mineral nitrogen input from the moss-cyanobacteria associations into northern boreal ecosystems is at least equal to that which comes from the atmosphere -  it is a very significant contribution.  

Fungus on a moss

Sorting through some old photos this evening, I can across this - taken on my in-laws lawn in Cornwall on New Year's Day 2012. This appears to be the basidiomycete Arrhenia retiruga growing on Calliergonella cuspidata. Has anyone else seen anything similar?

Calliergonella lindbergii on tarmac

Our lane gets little traffic and has a well-developed moss strip along its centre.  Didymodon insulanus and D. nicholsonii are the dominant species, and I have even found D. nicholsonii with abundant ice crystals growing all over it so I don't think its increase in lowland Britain is (solely) the result of climate change.  Anyway, yesterday I noticed some Calliergonella (=Hypnum) lindbergii among the mosses on the tarmac, neatly linking two previous Blog threads.

Calliergonella maps

In response to Graham's earlier post here are the distributions of our two Calliergonella species (MapMate data only).

Calliergonella (Hypnum) lindbergii

For the first time in ages I was allowed to get away from the desk to a meeting just north of Pontneddfechan (Brecks).  Whilst walking back to car I remembered that C. lindbergii likes to grow in short-cropped turf by tracks/roadsides and just like the stuff I was walking past.  I hadn't seen it for quite some time but about 15 seconds later there it was poking up between the grasses!   I notice that the NBN seems to show quite a few gaps for this moss in Glam, so if some of you are not aleady aware of where it might grow here are a couple pics to help locate it.

by the way George, apologies for not making myself known to you at meeting last week - by time I realised who you were and meeting had ended I got highjacked by Rebecca and had to discuss work.

Oh well, looks like I have lost my blog virginity - time for an imaginary cigarette!