Epiphytes on the move

I always like to find Frullania species when I'm out bryologising. Both Frullania dilatata and Frullania tamarisci are fairly common species. I just like the colour.

Frullania tamarsci near Blakeman's Law

In North-east England, most bryophyte epiphytes become more common the further west you go. Areas with high rainfall, especially sheltered, humid gorges are generally the best places. Many species are also sensitive to certain types of air pollution and as a result large areas of eastern England have lost most of their epiphytes. Nowadays the air is no longer polluted from as much coal-burning as it was in the past. It has taken a few decades for epiphytes to recolonise formerly heavily polluted areas, but in the last 10 years or so several species have begun to recolonise eastern areas at a dramatic rate.

In the south-east of England and East Anglia, this phenomenon has been fairly well studied and documented, as there are quite a few active bryologists down there. Up here, we have more bryophytes but bryologists are very thin on the ground and recent recording has been so patchy that we just don't know yet which species are recolonising and how fast. It seems like some of the species showing the greatest recent increases in the south are not so prominent here, at least yet. On the other hand we probably have other species that are recolonising our area, that are still rare in the south.


Ulota phyllantha at Brown Hill

About 10 days ago I found lots of Ulota phyllantha on willows and rowans in a sheltered valley within Kielder Forest south of Stonehaugh. This is quite uncommon in Northumberland, but I found it on lots of trees in various places within about a mile of where I took the picture. I've no idea if it has been there a long time or if it has recently recolonised. Andy McLay recently found it in Co Durham - the first record there for over 100 years. I told him I wouldn't be surprised if he found some more and a couple of days later he found some at another site.


Orthotrichum pulchellum at Brown Hill

Orthotrichum pulchellum is one of the species in the south that has shown a big recent increase. I've been puzzled why we haven't found more of it up here. There was a big population of it on about 5 or 6 trees in the same valley south of Stonehaugh. For an Orthotrichum it is quite distinctive: it is the only one whose leaves curl up when they are dry; it has a very neat overall appearance; it is always quite small; the base of the calyptra usually has dark dots all round it; and the peristome theeth are orange.

Hopefully it will start turning up now in some other new sites.

John