Thursday, 29 September 2016

Ty-du Moors SSSI

I spent a fascinating and enjoyable day on this Cardiff fen with Julian Woodman, trying to work out why base-rich areas (with Eriophorum latifolium, Epipactis palustris, Gymnadenia sp. and Triglochin palustris) are becoming increasingly dominated by Sphagnum subnitens and Aulacomnium palustre.  We concluded that more work is needed, with input from Gareth Farr (what a shame you couldn't join us today, Gareth), but probing revealed over 2.5m of peat near the centre of the moor, whilst test coring showed that the base-rich areas and associated Juncus subnodulosus fen are on continuous peat, whereas the edges of the moor with Carex acutiformis fen has a layer of organic-rich clay-silt above the peat.

Campylium protensum is locally abundant in the remaining good, base-rich areas, along with Fissidens adianthoides, Plagiomnium ellipticum, P. undulatum and one stand of Dicranum bonjeaniiChiloscyphus pallescens and Cratoneuron filicinum were only in one area.  Poached damp grassland held Pseudephemerum nitidum and one patch of Ephemerum serratum

A check of surrounding Willow scrub was worthwhile, with a fruiting patch of Pylaisia polyantha on one Willow, as well as commoner epiphytes.  I think this is the 2nd Glamorgan record, following one on south Gower.  It's a pity that I found this epiphyte after George had left us, following his visit in the morning.  Nearby Alder carr held a peculiar tiny, narrow-leaved moss with gemmae on the leaf tips, forming an extensive patch on a well-rotted log.  I'm 99% certain this is Plagiothecium latebricola. {sorry about the bad iPod photos, I wish I knew how to rotate them in Blogger}.

Julian and I ended the day with a visit to some wonderful damp arable fields that Nick, the owner of Ty-du Moors, manages.  We relocated the Anthoceros that Julian and George saw last autumn, and I have a specimen to measure (though it's 99% certain to be A. agrestis).  Alongside were several thalli of Phaeoceros sp. (probably P. carolinianus but needing more study), and abundant Riccia glauca and Fossombronia sp.

All in all a good day, and I hope a boost for tetrad ST17E.


  1. Some great records there, plus a couple of species which I still need to catch up with. Sounds a fascinating site.
    Today was yet another day in the Kenfig scrapes failing to find Petalophyllum, but enjoyable all the same and plenty other records produced.

  2. It's a fact that every time one has to leave a site early there is something good found later in the day - or in this case several good things! Some really great records there and I'm sure this will be a big boost to the current ST17E total of 66 taxa. Pleased you found the hornwort too...just a shame I couldn't stay longer.

  3. yes I was gutted I couldnt come along ! There are lots of glacioflucial sands and gravels and maybe installation of dipwells near base rich area could inform us of the water supply to the centre of the bog ? Let hope we can meet up on the Nedern brook in the future !

  4. should read till not glaciofluvial sand and gravel from map, however boreholes report big sequences of S&G in area to north. Base richness could come from localised areas in superficials or more likely underlying bedrock, still tbc.

  5. I wish I'd had a longer corer - just had a 1m test corer and 5m of probes with me - to get to the basal layers. The shallow peats were underlain by clayey, gravelly stuff, which I guess could be repeated across the wetland. The key impression for me is that it's a deep peatland, with lateral flows seemingly limited to the margins, so something other than rainfall is feeding the central basic areas otherwise there would be an ombrotrophic bog. Lots of future fun!

  6. BGS have a russian 10m corer , which we used at Pant y llyn with Jamie. it retrieves really nice core that can be stored and photographed and properly analysed. Maybe there are areas of high permeability material or thin clays that allow more base rich water to flow upwards into the bog from the bedrock or superficial aquifers, still thats no more than speculation at this point. Id be more than happy to do a day of coring at the site to get some proper stratigraphy, we could also test the water in that area to see if it 'looks' like groundwater.