In contrast to the Brecon Beacons - which Graham and I surveyed systematically in the early/mid 2000s - the Black Mountains are very under-recorded. They have relatively fewer crags than the Beacons, but those which are present hold some very base-rich rock. Star species include
Seligeria patula and
Scapania calcicola on Tarren yr Esgob, an old record of
Amblyodon dealbatus, and even a historic claim of
Myurella julacea. We hope to fill in some gaps in recording this year, and I made a start on two days in early-mid January 2018.
My first day was spent in Monmouthshire, where I filled in three marginal tetrads: the fragmentary SO23R and SO32E held fewer than 20 species each, but SO23V was pretty rich, with well over 100 species. I walked up on to the Hatterall Ridge from the east, between the Red Darren and Black Darren in Herefordshire. Once on the ridge I marched north to the northernmost point of VC35, which is marked by a tiny cairn. The northernmost bryophyte in the county turned out to be
Rhytidiadelphus squarrosus, and half an hour of combing the dry blanket bog produced just 11 species. Surprise highlight of the area was a patch of leggy Bilberry at >600m altitude that sported 10+ tufts of
Ulota bruchii and a tuft of
Orthotrichum pulchellum!
The blanket bog on the Hatterall Ridge is mostly very dry and degraded, but I made a few DAFOR lists as I worked my way south. Highlights were a 1x1m mound of
Sphagnum capillifolium rubellum at SO275311, 10s of square metres of
S. cuspidatum and
S. papillosum in an area of pools at SO281306, and a few shoots of
Cephalozia connivens in the latter area. Cowberry and Crowberry were prominent features of the area.
A contrast to the blanket bog/moorland was provided by the hillside above Trevelog, at 420-450m altitude; this accounted for the majority of the bryophyte diversity in SO23V. There were Old Red Sandstone boulders with
Ptychomitrium polyphyllum,
Seligeria recurvata and
Tortella fasciculata, a deep valley with
Entosthodon obtusus,
Ditrichum gracile,
Gymnostomum aeruginosum and abundant
Conocephalum salebrosum, and a series of base-rich rills with
Philonotis calcarea,
Palustriella falcata,
Jungermannia exsertifolia,
Leiocolea bantriensis,
Plagiomnium ellipticum and
P. elatum. Star find was some dense patches of
Riccardia incurvata alongside one of the rills, new for the Black Mountains and VC35.
After these riches I reckoned the tetrad was well-covered, so climbed back up to the ridge so as to head southwards to SO32E.
En route I noticed a frozen flush high on the hillside in SO22Z, so headed for it. My logic was that if a spring/flush was cold enough to be frozen when the rest of the hill had thawed then it should hold something rare. I followed it upwards, and found two extensive patches of
Sphagnum platyphyllum at SO286297 & SO287297 - my logic had proved right! This was a new species for the Black Mountains and VC35, and is a long way south of its nearest colonies in mid Wales and the Long Mynd. It was also the most well-marked
S. platyphyllum I have ever seen, with large apical buds, pale stems, large stem leaves and regularly monoclade shoots.
SO32E still beckoned, and on my way there I spied another rushy spring on the ridge edge. This too held
Sphagnum platyphyllum at SO297287, as well as
S. capillifolium rubellum and
S. papillosum. The final fragmentary tetrad produced 17 species, which was all that could be expected from a few hundred square metres of dry, patch-burnt blanket bog. All in all it was a good day!
