01 May 2015

An Equisetum to look out for.....

I recently visited the limestone ridge near Carmel, Carmarthenshire, much of which is now a National Nature Reserve and an area for which I have fond memories,  it being the first SSSI that I notified (with intense opposition), back in 1986. My recent visit was for relaxation rather than work and one particular plant that I wanted to see was a rather rare horsetail.
In 2003, in some wet, calcareous flushes along a path at Pentregwenlais and SW of Cilyrychen Quarry, I noticed a rather robust Equisetum variegatum, which puzzled me and I took a portion home to identify, I made it to be Equisetum variegatum var. wilsoni but there was a problem - this latter variety was only supposed to occur in SW Ireland. Advice from the National Museum Wales suggested that I was incorrect in my determination, but they kindly agreed to send the specimen off to Christopher Page (one of the best pteridologists in the UK and author of The Ferns of Britain and Ireland).
To my pleasure, he noted, "This is fascinating. Although smaller than the type, it answers exactly the exceptional smooth meristem internode of the Killarney material. I confirm it as E.variegatum var. wilsoni Newman. This must be the first record outside Ireland".
It is vital that sufficient management is carried out by NRW, to ensure that this biographically important population is not lost to scrub encroachment.
There is already an Irish flavour to Carmel Woods, with its `turlough` (ephemeral lake on limestone) at Pantyllyn - the only formally recognised UK example - and another taxon with a south-westerly (`Lusitanian`) hint is the rare harvestman Sabacon viscayanum subsp. ramblianum. It occurs deep in damp, humus-rich block scree at Carmel (and also other sites on the Carmarthenshire limestone), as well as under loose rocks in damp gorges elsewhere. In the past it was suggested to be an introduction, after it had been initially found on Gower and near Cardiff, as it was near some man-modified sites (quarries etc). I refute that assumption - in my view it is typically a species of rocky `cwms`and other persistently damp places and again one of an assemblage of organisms that perhaps colonised the British Isles via a western route along the Atlantic seaboard (rather than the over depended on Dover/SE England/North Sea routes). Incidentally, `Viscayana` (as in Sabacon`s name) was a Roman province of northern Spain - this harvestman was first described from a cave in the foothills of the western Pyrenees. This western Pyrenees/Northern Spain Basque country is now believed to be also the origin of much of the earlier human colonists of Britain - the older genetic groups that achieve greatest incidence in Wales and, more particularly, Ireland.
I too must have `an Irish touch` (but not genetic affinity!) as, about twenty years ago, I was again lucky enough to find another first UK record (outside Ireland) - the woodlouse Oritoniscus flavus, found at the edges of wet ditches at Llwynhendy/Bynea (c N of WWT Penclacwydd). It has subsequently been discovered at a locality in SW Scotland, as well as the long-known populations in Eire.

                                  Above: the Carmel horsetail. Click on the photo to enlarge.

5 comments:

Barry Stewart said...

I remember you telling me exactly where to find the Oritoniscus and sure enough it was exactly as described. You also kindly showed me the beautiful Sabacon. O'Morgan's Horsetail is one I've yet to see...

Ian Morgan said...

If you want to see it, it`s easy to find. Go to Pentregwenlais and park in the `main lane` (plenty of places). Take the path going c N at SN609163, walking briefly through a bit of an open area for a few yards, then follow the narrowing path down to just before an old lime kiln or similar structure. The Equisetum is just before that fenced-off structure on the left-hand (W) side of the path in wet flushes. I hope that CCW/NRW are looking after it!
O`Morgan nearly had an `Irish hat-trick` this morning, spotting a leprechaun in Llanelli but, on close examination, it turned out to be a discarded garden gnome!

Jamie Bevan said...

I'll sort out the scrub control around the Equisetum

Ian Morgan said...

Jamie....I was sneakily hoping that you`d read the blog - thanks. If you want to meet up there, no probs.

Jamie Bevan said...

IKM...that's the way I took it ;-) Let's meet up soon with Nigel Stringfellow!