Saturday, 17 February 2018

Treasure in the bracken


I visited Craig y Castell and part Craig y Cilau near Llangattock last week – I didn’t intend to look at bryophytes, but it is difficult to switch off completely at such a rich site. 

With the bracken now died back and partly broken up by grazing animals, I was surprised just how many scattered rocks/boulders are present in some areas, with all but the largest tending to be completely hidden by the bracken in summer.  


 Most of the big blocks are limestone with a lot of the smaller ones acidic grits and sandstones.   As I wandered around I noticed each acid rock seemed to have a slightly different bryophyte flora to its neighbours.  One of the largest had a nice colony of the lichen Sphaerophorus globosus, whilst others had big patches of things like Racomitrium lanuginosum, Lophozia ventricosa, Tritomaria quinquedentata, Barbilophozia attenuata and Campylopus fragilis was present on a few.    About half a dozen rocks also supported colonies of Tritomaria exsectiformis /exsecta (reddish-brown and green patches in the photo). 
A few years ago Sam and I recorded T. exsecta from nearby woodland, so I checked one of these colonies and sure enough the rounded gemma showed this too to be exsecta.  

Perhaps all the colonies I spotted were exsecta?.   

The limestone blocks and more lime-rich sandstone blocks also have some interesting things, mostly lichens, but there are often large patches of Neckera crispa and Scapania aspera and I also spotted things like Leucodon sciuroides (probably new to the site), fruiting Tortella tortuosa, a form of tortuosa with very fragile leaves and a large block sported five tufts of fruiting Entosthodon muhlenbergii.


Away from the boulders and bracken other things of interest, included a sheep’s skull with a small tuft of Orthotrichum pulchellum, some broken branches of a hawthorn below Craig y Castell had what I presume is Agyrium rufum, 


which has been recorded from the nearby NNR in the past.  Ledges in a quarried area had a  few tufts of Encalypta vulgaris and a dark scum on a damp quarry face on closer inspection was found to be Seligeria patula (presumed).  A few patches of the scarce lichen Solorina spongiosa  
were also growing on an eroding bank by a path.   Now that days are getting longer, some vascular plants were starting to show, with endemic hawkweeds beginning to put out new leaves, rue-leaved saxifrage flowering and I also spotted a single plant of Hutchinsia
and some sort of cabbage has found its way onto the cliffs
.   

In future I will pay more attention to boulders that are hidden by bracken in summer. 

2 comments:

  1. Great site with a lovely selection of species. Tritomarias are fabulous liverworts.

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  2. Definately a place any botanist should visit at least once in their life.

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