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.
Great site with a lovely selection of species. Tritomarias are fabulous liverworts.
ReplyDeleteDefinately a place any botanist should visit at least once in their life.
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