Holiday Bryophytes - lots of leskeas

Alpine habitat, La Tofane

We were in the Dolomites in July this year, our third visit to this fabulous mountain range in Northern Italy. Most of our attention was paid to the spectacular alpine flowering plants but we did note a few bryophytes.
 The subalpine forests have an extraordinary abundance of Rhytidiadelphus triquetrus and Hylocomium splendens (and lots of orchids, including Lady's Slipper) in stark contrast to our local, acidic Sitka forests with their abundant carpets of Rhytidiadelphus loreus. 

Rhytidiadephus triquetrus and Hylocomium splendens in spruce forest near Cortina

The geology is predominantly limestone and lots of typical calcicole bryophytes are represented plus some really nice mountain species that are rare in Britain. In the province of Belluno, between Cortina D'Ampezzo and the Falzarego Pass, some excellent trails took us above tree-line into alpine tundra where there were wallcreeper.  In the rocky tundra below La Tofane Ptychodium plicatum (Plaited Leskea) was growing with Saxifraga oppositifolia (Purple Saxifrage) on some sheltered limestone boulders. 

Ptychodium plicatum and Saxifraga oppositifolia, la Tofane

H and Mark on Wallcreeper twitch above Falzarego Pass

On a hike to the Rifugio Locatelli from the famous Tre Cime di Lavaredo we encountered small parties of snow finches flitting about rocks covered with Pseudoleskea incurvata.  Later, in the mountains above Selva in the Val Gardena we found some Pseudoleskea patens (Patent Leskea) which gave us a good opportunity to compare these very similar species. In the end we had to bring samples home to examine the shape of the mid-leaf cells to confirm their identities.

Pseudoleskea incurvata with Salix herbacea (Dwarf Willow) near Rifugio Lavaredo

Pseudoleskea patens, Selva

The short walk to Baita Monzoni in the Val San Nicolo near Pozza di Fassa follows a forest road through a moist, mossy subalpine forest. Bartramia halleriana (Haller's Apple-moss) and Campyllophyllum halleri (Haller's Feather-moss) were on the base rich rocks here - the latter is a Red DataBook moss in the UK. Nearby on a large limestone boulder at the side of the road we noted a large, striking mat of Pterigynandrum filiforme (Capillary Wing-moss). From Monzoni the trail climbs up, eventually, to the Pas de la Sele and allows access to an outstanding alpine flora which includes lots of saxifrages (e.g. the endemic Saxifraga depressa) and other nice things like Papaver rhaeticum (Alpine Poppy), Phyteuma sieberi (Sieber's Rampion), Primula glutinosa (Sticky Primrose) and Ranunculus glacialis (Glacier Crowfoot).

Bartramia halleriana near Baita Monzoni

Bartramia halleriana with capsules

Campylophyllum halleri near Baita Monzoni

Pterigynandrum filiforme on a boulder near Baita Monzoni

Pterigynandrum filiforme Baita Monzoni

On a trip to Sottogudo we walked along a narrow road through a spectacular gorge where  Orthothecium rufescens (Red Leskea) was hanging from dripping limestone outcrops. There were some nice clumps of Selaginella helvetica here too. 

Orthothecium rufescens, Sottogudo Gorge

Orthothecium rufescens, Sottogudo Gorge

Selaginella helvetica, Sottogudo Gorge

Although the landscape of the Dolomites is dominated by limestone there are some extensive cliffs and outcrops of more acidic igneous rock which support a different flora, e.g. on and around Forcia Neigra near Alba. Our attention was stolen by some nice cushions of Eritrichium nanum (King-or-the-Alps) but we also noticed some conspicuous dark cushions of Grimmia montana (Sun Grimmia).

Grimmia montana, Forcia Neigra

Don't always believe what the books say

Just flicking through the New Atlas and glanced at some of the comments regarding production of sporophytes in some species.   As recorders don't always make a note of whether a species was fruiting or not, it seems the BRC bryophyte database has very few records of fruiting in some very common species, which can then be interpreted as some species producing fruits only rarely.   Many of the common dioicous pleurocarps such as Calliergonella cuspidata, Rhytidiadelphus squarrosus, R. triquetrus, Hylocomium splendens, Pseudoscleropodium purum and the like are often reported in the text books as fruiting only rarely.  This may be true taking Britain as a whole, but we have found in south Wales that some of these species seem to fruit reasonably often.  I usually make a special search for fruits if I come across large patches of pleurocarps and it is surprising how often they are present - late winter seems to be a good time to look.   The next time you are walking across a dull bit of heathland with abundant Pleurozium keep an eye open for fruits - although this moss does seem fruit less often than some of the other species mentioned above.    You may have to dig around a bit in patches of some species - e.g. in Breutelia setae are very short and fruits hidden well inside hummocks; on Pseudocleropodium fruits appear to be produced on the previous years growth and so despite having a long seta the capsules can still be hidden amongst stems.

I have still to find fruits on Climacium in Wales (seen them once in Yorkshire) and the only time I have seen them on Rhodobryum was when I examined an old herbarium packet containing a specimen collected near Carmarthen, but I live in hope.

        

Rhytidiadelphus triquetrus further afield

The distribution of Rhytidiadelphus triquetrus in Glamorgan is partly elucidated by examination of maps from three other pretty well-recorded S Wales VCs. 

It has a very inland distribution in Pembs, largely avoiding the coast (except for a handful of very sheltered lane banks or churchyards, perhaps introduced with wreaths in the latter).

Colonies are widespread in Carms except around Llanelli and Carmarthen.  The strongest populations are on lane banks in the northern half of the county from Clunderwen to Llandovery.

Finally in Monmouthshire it is scarce except in the Black Mountains, with a few lane bank colonies around the Trellech plateau.

The first Atlas said that pollution had caused declines in Rhytidiadelphus triquetrus, and that would seem to make a lot of sense judging by its distribution in south Wales.  Roll on the time we can publish a S Wales tetrad Flora to really display these patterns!!

Rhytidiadelphus triquetrus

I was out in southern Ceredigion yesterday (Capel Dewi, just north of the Teifi) doing Brown Hairstreak egg surveys, and was struck, as always when doing BH surveys in SW Wales, by the abundance of R. triquetrus on lane banks.

I've still to record this species in Glam! Barry, could you post a map please? Maybe one for each of the Rhytidiadelphus species if you have time. Thanks.