Wednesday, 27 April 2016

Blaen Pig iron spring

Johnny and I went hunting for fossils today (as you do... he's only in Kindergarten four days a week, and Clare was working in Devon so I took the day off).  I wanted to try somewhere in VC35, so I could keep an eye out for bryophytes, and as my home patch is fossil-free Old Red Sandstone I headed west towards the Coal Measures at Blaen Pig (N of Gilwern Hill).  This is a vast area of spoil, some of which is very old whilst other areas are much more recent.  I have searched it 5 times over the last 16 years, but there are still many bits that haven't been checked bryologically.

I have seen small, dense Dichodontium on the coal tips a few times before, as well as on ledges on upland limestone in Carms & Brecs, and I think that Charles has reported similar plants from NPT.  It seems to match the old "var. fagimontanum", and looks much more distinctive than the ever-intergrading pellucidum and flavescens.  There were several patches on damp, slightly basic coal spoil near the foot of the tips.

After a while we came across a spring, where extremely iron-rich water bubbles out from below a tip (but perhaps associated with a natural break of slope).  This held Potamogeton polygonifolius, Eriophorum angustifolium and other common flush species (but no Pinguicula that I could see), plus Campylium stellatum var stellatum new for the tetrad (the mega-rich SO21K) and several common sphagna.  For a while, the highlight was potential Sphagnum teres, but I have reluctantly concluded it's just one of the peculiar brownish, scarcely squarrose forms of Sphagnum squarrosum that one occasionally encounters.

Johnny enjoyed the iron spring, and also a few small fern fossils


  1. Sam, good to see you had someone with you who was able to show you how to do this bryology thing properly...

  2. Yes Sam, it looks similar to some of the dense swords of Dichodontium that populate the damp grit at the sides of forestry tracks in NPT.