Visited by IK Morgan & RN Stringer, 21.6.2013
The main purpose of the visit was to see whether we could
relocate serrated wintergreen Orthilia secunda, last recorded at this
locality by AH Trow and JH Salter in 1905. According to the Flora of Glamorgan
(Wade et al, 1994: 151) previously, in 1892, Trow had found it at one
locality and, on the 1905 visit they found it at a second site at Craig-y-llyn,
but with Trow noting in 1911 that the 1892 site was `almost inaccessible now`.
IKM had visited Craig-y-llyn with Julian Woodman in July
1997 to look for Orthilia and other plants, but on that rather cursory
visit, Orthilia was not seen (though other species of interest were). The notes relating to Orthilia in The Flora of Co
Fermanagh by Ralph Forbes and Robert Northridge, newly published in 2012 acted
as a catalyst for IKM to try to search again for Orthilia and it was
decided to make Craig-y-llyn the target for one of our weekly botanising visits
in June. The excellent `Fermanagh Flora` contains some very comprehensive and
useful notes (on pp377-8) regarding the occurrence of the species in that
Northern Irish county, saying that it is found `in dense clonal patches….in
crevices….on dolomitized sandstone scarps, and scattered in steep submontane,
mossy, Calluna-Vaccinium-dominated heathy slopes`. They also remark that
`when one has got one`s eye in for it, the rather pale, grey-green,
wintergreen, serrated leaves can be picked out amongst other foliage and moss
all year round`. It flowers only very sparingly in Co Fermanagh and we can
assume the same to apply to the more southerly site at Craig-y-llyn (and Craig
Cerrig-gleisiad in Brecs, where it also has been recorded) – so one has to
search for the vegetative clonal patches, hidden under Vaccinium or Calluna. As we approached Craig-y-llyn via the track to Llyn Fawr on
21.6.13, we scanned the amphitheatre of cliffs for good rock faces and gullies
to search. We had intended to start near the eastern part and work westwards
and, accordingly we ascended the steep talus slopes that are covered in dense Vaccinium
myrtilus and other vegetation. This climb itself was quite tiring. En
route, old empty 2013 `tent nests` of bilberry pug Pasiphila debilata
were common in this area of bilberry, most were brown and withered, with the
larvae having vacated them, but a few individuals were still to be found,
perhaps reflecting the late, delayed season this year. An adult latticed heath Chiasmia
clathrata clathrata was also seen, as well as the common beetle Phyllopertha
horticula.
Upon reaching the intended first gully, we realised that
what had looked reasonably easy from down by the lake was actually quite
difficult. This first gully (at
SN918030) was very floriferous, with flushed areas holding an attractive suite
of plants akin to an Alpine meadow, with abundant Geum rivale, Angelica
sylvestris, Sanguisorba officinalis, Valerianella officinalis,
Succisa pratensis and Tussilago farfara, many of which were in full
flower and being visited by bumblebees that included the very local Bombus
monticola (as well as the common B. pascuorum). On rockier areas,
were strong, flowering plants of Rhodiola rosea and some clubmosses. It was when we started to work our way laterally along the
cliff faces that we fully realised how difficult it would be, some sections
being relatively easy, but others difficult or dangerous, requiring descents
and ascents to avoid steep drops that may not be apparent amongst the deep
swathes of Vaccinium. It also proved difficult to climb some sections of
actual cliff face to search for Orthilia amongst the Vaccinium.
Progress was slow but we worked westwards, passing groups of whitebeams Sorbus
porrigentiformis and searching for Orthilia, though again, we could
not climb most outcrops above.
After a few hours covering a disappointingly short distance,
we decided to call it a day and descended back down to the lake/reservoir. How
little we covered was apparent when we looked back at the cliffs, the area
being that represented in the accompanying photograph below. We only covered
that area of cliff eastwards of the prominent tree on the skyline!
We see no reason why Orthilia does not survive at
Craig-y-llyn but it will need perhaps repeated efforts, or collective efforts
by groups of fit botanists focusing in on this species. In the days of Trow and
Salter, the general area would have been sheep-grazed with only those areas
inaccessible to sheep holding luxuriant vegetation, on ledges and the like.
Perhaps these botanists were likely to have targeted these ungrazed areas as
likely to hold species of interest. The fencing off of the area around the lake
many years later, presumably linked to the establishment of the forestry below
has resulted in a resurgence of vegetation –itself of great value in our
overgrazed uplands (and hence the lovely herbaceous swards on the
afore-mentioned flushes), but it does make traversing the area a little more
difficult and the locating of Orthilia even more so!
As well as the suggestions given above with regard to
locating Orthilia, it may be worth considering a (snow/frost-free) late
winter visit, when much of the vegetation has died back and when perhaps its
grey-green hue may stand out amongst the darker green bilberry? In June, the bilberry can also look fresh and very slightly
glaucous (as well as having finely serrated leaf margins), so beware!
Craig-y-llyn is a wonderful place and I`m sure that it will yield other
noteworthy natural history records of all taxonomic groups - after adequate
searching. Some plants of Dryopteris carthusiana were seen near
Llyn Fawr at SN91939 03470.
Forbes, R.S. & Northridge, R.H. (2012) – The Flora of
County Fermanagh. National Museums Northern Ireland.
Wade, A.E., Kay Q.O.N. & Ellis, R.G. (1994) – Flora
of Glamorgan. The Natural History Museum, London.
I.K. Morgan & R.N. Stringer, June 2013.
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