Slim pickings in the Vale

Parts of the Vale are still chronically under-recorded for bryophytes. The latest VC41 tetrad map shows a particularly bad white hole in SS97 and ST07:

Looking at the OS maps and aerial photos for some of these unrecorded tetrads it became obvious why no bryologists had bothered to record there - a mix of improved grassland and large arable fields, with a few lanes passing through and a distinct lack of woodland. Challenging territory indeed, but feeling rusty after the summer hiatus it seemed a good place to kick off the bryophyte recording season when I had a day off work last week. Not too many species to tax my brain.

I visited three tetrads on a day of sunshine and showers, with some lengthy downpours meaning time was lost while sheltering in the car. I started off at Llysworney, which had a bit more habitat variety than some of the other areas thanks to the village streets and walls, and Worney Wood - a new wood planted by the Woodland Trust. The woodland would presumably have been a couple of boring rye grass fields until it was planted a few years ago. Now it supports young trees quite rich in epiphytes, though with nothing of note except for some Porella platyphylla and Didymodon sinuosus on an old field boundary Ash. Tetrad SS97S has now moved along from 3 to 37 bryophyte species.

Much of the day was spent walking the lanes and footpaths in SS97R, which at least succeeded in putting this tetrad on the bryological map with 49 taxa recorded. It was a bit of s struggle though. The arable fields had been recently sown with winter cereals, but a sample collected from a small area of unploughed margin produced three tuberous Bryum species: B. rubens (large knobbly red tubers), B. ruderale (large tubers & papillose violet rhizoids) and B. violaceum (smaller tubers & smooth violet rhizoids - photo below).

To end the day there was time for a brief stop at Llanmihangel churchyard before the heavens opened again. This small churchyard, tucked into a valley bottom, proved to be the nicest spot of the day, and produced a few species not seen at the earlier sites: Cirriphyllum crassinervium, Lophocolea bidentata, Thuidium tamariscinum and Plagiochila asplenioides (the latter growing on a stone grave). SS97V was another tetrad that hadn't been recorded previously, so all 20 species were new.

A feature of the day was the abundance of Anomodon viticulosus on laneside walls and a few hedgerow tree bases. This species is proving frequent in the lime-rich Vale and I look forward to putting more dots on the map on future visits.

I enjoyed the day despite making only 128 bryophyte records and failing to take any tetrads past the 60 mark. No doubt a spring visit would add a few more Orthotrichum, Ulota, etc, but is it worth the effort? I think the time would probably be better spent elsewhere.

Porella arboris-vitae revisited

I was working on Old Castle Down this morning, and couldn't resist a quick stop to admire the fine patch of Porella arboris-vitae which grows on a lump of limestone here (spot the Mottled Grey resting on the same rock).

I was pleased to find a couple of additional patches of the Porella on adjacent rocks (highlighted in photo below - the original patch is on the right). Somehow I'd missed these on previous visits.

I also checked a nearby limestone wall, but although it was wonderfully mossy, including big sheets of Porella platyphylla, I couldn't find any more arboris-vitae.

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.

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.