Bryophyte season kicks off in the Lye Valley

In a joint effort to be more organised and transparent, this season all our meetings are on the blog calendar! We will be emailing around the details of meetings a few days in advance, if you are on David's botanical mailing list, you'll get them. If not, get in touch!

Our first meeting of the season was to the eastern suburbs of Oxford to visit the Lye Valley (SP5405), incorporating the Local Nature Reserve of the same name. This site used to be known as Bullingdon Bog, and as such is something of a locus classicus for Oxonian botany. It was, for example, the site where L'Obel made the first record of Parnassia palustris for Britain; it was recorded by Sibthorp and Boswell, and featured in early ecological work on calcareous fens by Roy Clapham (later lead author of the primary British Flora in use from 1958 up to the early 90s, when it was superceded by Stace).

A view along the Lye Valley LNR. (O.L Pescott, CC0).

It seems that we are lucky to still have the site in the reasonable condition that it is in. Eustace Jones in the early 1950s commented that "Bullingdon Bog which must once have been an ideal example of a calcareous valley bog, is now a disturbed fragment lying in the middle of an Oxford housing estate, and obviously cannot survive much longer." Although the site was scrubbed over in recent years, and the valley sides slumping due to scouring of the valley bottom by a storm drain outflow directed along the stream, excellent management work has taken place in recent years, and is gradually restoring the valley mire to its former glories (thanks to David Morris for this information).

Bryologists assemble! (O.L. Pescott, CC0).

But to the bryophytes! We dropped into the valley from Coverley Road, recording the woodland and along the stream before the beginning of the LNR proper. Many common species were quickly found, including Tortula subulata on friable soil, and Rhyncostegiella tenella on stone. Along the stream the thallose liverworts Lunularia cruciata and Pellia endiviifolia were growing in close association at the bottom of a concrete embankment. An odd amblystegioid growth was also scraped from concrete, which, under the microscope, seemed to match descriptions of the coastal variety of Amblystegium serpens var. salinum. This, however, would be an odd turn-up for Oxford, and must await confirmation from the BBS Recorder for Mosses! Subsequently an old Hawthorn turned up a rich crop of epiphytes, including the ever expanding (and beautiful) species Orthotrichum stramineum and Syntrichia papillosa. An uncertain Ulota was later checked at home, but turned out to be the commonest taxon (at least locally) U. bruchii.

After lunch the reserve proper was tackled, and a new list was begun to ensure that records made would be traceable directly to the LNR. Many epiphytes and common species were again quickly added, including a number that chose to grow on the synthetic wood of the reserve boardwalk (Syntrichia latifolia, S. montana, S. virescens, Orthotrichum affine, O. diaphanum, among others). Next was the fen proper, and many of our expected species began to accumulate (Plagiomnium elatum, Cratoneuron filicinum, Palustriella commutata, P. falcata, Campylium stellatum, Fissidens adianthoides etc.) All previously known from the mire, but all lovely to see thriving. The curious epiphyte Platygyrium repens was also found on a pollarded willow along the stream. Deciduous branchlets of very fine leaves give this species a fuzzy appearance in the field.

Platygyrium repens at Lye Valley. (O. Pescott, CC-BY).

Some known species we failed to refind (e.g. we did not relocate Drepanocladus revolvens or Climacium dendroides), but many other species were added to the site list. A productive day, and a good start to the season.

The list of unique species seen was as follows:

?Amblystegium serpens var. salinum	Platyhypnidium riparioides	Brachythecium rivulare
Amblystegium serpens	Rhynchostegiella tenella	Bryum pseudotriquetrum
Barbula convoluta var. convoluta	Rhynchostegium confertum	Calliergonella cuspidata
Barbula convoluta var. sardoa	Schistidium apocarpum s.l.	Campylium stellatum s.str.
Brachythecium rutabulum	Syntrichia laevipila	Cirriphyllum piliferum
Bryum capillare	Syntrichia papillosa	Ctenidium molluscum
Bryum moravicum	Tortula muralis	Dicranoweisia cirrata
Cratoneuron filicinum	Tortula subulata	Didymodon fallax
Cryphaea heteromalla	Ulota bruchii	Fissidens adianthoides
Didymodon sinuosus	Zygodon conoideus var. conoideus	Fissidens incurvus
Fissidens bryoides	Cololejeunea minutissima	Orthotrichum lyellii
Fissidens taxifolius	Frullania dilatata	Palustriella commutata s.str.
Homalothecium sericeum	Lophocolea heterophylla	Plagiomnium elatum
Hypnum cupressiforme var. cupressiforme	Lunularia cruciata	Plagiomnium undulatum
Hypnum cupressiforme var. resupinatum	Metzgeria furcata	Syntrichia latifolia
Kindbergia praelonga	Metzgeria violacea	Syntrichia montana
Orthotrichum affine	Pellia endiviifolia	Syntrichia virescens
Orthotrichum diaphanum	Radula complanata	Thamnobryum alopecurum
Orthotrichum stramineum	Platygyrium repens	Cephalozia bicuspidata
Oxyrrhynchium hians Oxyrrhynchium schleicheri	Palustriella falcata	Lophocolea bidentata