some Grosmont finds

I haven't Blogged any bryophytes for ages I'm afraid, primarily because I didn't find much of interest over the summer despite fieldwork in N and Mid Wales.  Bea is now doing a drama class near Grosmont one day a week, and that gives me an hour or two in which to look for wildlife in the under-recorded hectad SO42, which is mostly in Herefordshire but includes 8 Monmouthshire tetrads.  Graig Syfyrddin, which rises to >400m, dominates the area and includes some Old Red Sandstone outcrops with species such as Seligeria recurvata and Tortula subulata, whilst the River Monnow meanders along the eastern edge.

First stop, last week, was a bend in the Monnow upstream of Kentchurch.  Old Red Sandstone outcrops held Plagiochila britannica, which is scarce on the county's sandstone, whilst steep soil associated with the outcrops (photo below) supported a tiny Fissidens that proved to be F. crispus (=F. limbatus).  The latter is the first county record for nearly 80 years, though I didn't photograph it in the field because it was getting dark.  Platygyrium repens was on a Crack Willow by the river.

Today's expedition aimed to cover part of SO42G, which includes a large conifer plantation between 100 and 300m altitude and a long section of the River Monnow, but no footpaths in either area.  I followed the only path, along the southern edge of the tetrad, and managed to rack up 48 species.  A return visit to roadside habitats should produce a few more, but it won't be possible to do the area justice unless I can pluck up courage to knock on some doors.  Anyway, the track to Upper Graig passed some arable land with Riccia glauca and Marchantia polymorpha ruderalis, some woodland edge with epiphytes, and then an old quarry where Grimmia trichophylla and Polytrichum piliferum were on sandstone.  Highlight came at the far end of my walk: a massive old Ash at SO42132232 held 50cm2 of Leucodon sciuroides. 

The distribution of Leucodon in VC35 is intriguing.  There are several populations on the Old Red Sandstone of Ysgyryd Fawr and the Black Mountains, a couple at Dingestow on Fraxinus and an Asbestos roof, two on sandstone roof tiles (Dingestow and Penrhos churchs) and one on Fraxinus in the Wye Valley.  I suspect it's overlooked on roofs, but it is clearly mighty rare here.

Wern Ddu (again) and Rudry

I made a trip to Wern-ddu yesterday to have a look for that bluetail, but on arrival there was already quite a crowd of assembled birders - some of whom cheerfully told me that they'd been there for several hours without seeing it. I lack the patience for that kind of thing, so quickly left to check out the much more easily twitched Fissidens limbatus found by Barry a few days earlier (thanks Barry...and you weren't exaggerating when you said it was tiny).

Fissidens limbatus

On the way there was a tempting pile of limestone rubble and spoil from past quarrying at Cefn Onn, which held plenty of (putative!) Leiocolea badensis and some more tiny Fissidens which will probably prove to be limbatus. A rotten log was covered in Nowellia, which might be new for ST18. As Barry mentioned, this north-facing slope is very mossy indeed and will surely reward a more thorough survey.

Probable Leiocolea badensis

Nowellia curvifolia

My main aim of the day was to look for Leptodontium flexifolium at Rudry Common, found here by  Roy Perry in 1974. I'm pleased to report that it is still grows here 43 years on!

Leptodontium flexifolium

Leptodontium flexifolium with deciduous stubby leaves at shoot tips

Leptodontium flexifolium habitat

It proved to be quite frequent on thin peaty soil around sandstone outcrops, mostly growing under slight overhangs. The main associate was Ceratodon purpureus (the overwhemingly dominant bryophyte here) with smaller quantities of Polytrichum piliferum and Campylopus introflexus. It looks like the whole site gets burnt regularly, which perhaps aids the persistence of the Leptodontium. This tetrad (ST18Y) should now be over 60 species.

Wernddu revisited

Well this time the Red-flanked Bluetail gave itself up readily and on our circuit back to the car I stopped briefly at what looked like the remains of an old lime kiln. Amongst some fruiting Leiocolea turbinata was the tiny Fissidens crispus (=limbatus). NB smallest tick marks below = 1μm and note protruberant cells.

Herzog's Pocket-moss at Penrice

note larger shoots of F. incurvus top right

I came across a lovely little colony of Fissidens crispus (=limbatus) comprising hundreds of fruiting plants on the shaded lane bank as you head down the hill from the village towards the estate (SS49208792). The main direct associates on the near-vertical bank were F. incurvus & Oxyrrhychium pumilum, the very long perichaetial leaves drawing attention to this tiny Fissidens, in which the shoots were just over 2mm long (left photo below, 8 units=2mm; right photo shows the small protruberant cells).

Herzog's Pocket-moss

A belated post from 28th March of Fissidens crispus (=limbatus) which I collected from soil encrusted rocks below the quarry face at Wern-halog, just east of Llanrhidian at SS50809349, found growing directly alongside F. viridulus and Oxyrrhynchium pumilum. The quarry exposure is part of the Millstone Grit Group (which I've always understood to be principally acid), but the plant assemblage shows there is some basic influence. You can get an indication of the protuberant leaf cells in the image below, but this was much clearer in binocular vision; this along with the small cell size making the id straight forward using Smith.