MOSSES AND LIVERWORTS IN THE WEST MIDLANDS

Mark Lawley

Why study bryophytes?

Mosses and liverworts make rewarding subjects for study by amateur naturalists because:-

1) The geographical distributions of bryophytes are poorly known compared with those of larger, more conspicuous plants and animals. Recording the hectad (10 km squares) - distributions of vertebrates and vascular plants in Britain nowadays consists of repeating earlier studies in order to elucidate changes in distributions during the intervening years. But the distributions of cryptogams and inconspicuous invertebrates are much more sketchily known, even in England, where natural history is traditionally popular. Away from the south-east, naturalists may easily find bryophytes not previously recorded for a county, or not recorded there for many years, and establish that some species are much commoner than hitherto realized.

2) It is also more rewarding to elucidate the geographical distributions of bryophytes than vascular plants because bryophytes are neither deliberately controlled nor planted by humankind. Not only do conservationists try to eradicate trees, shrubs, herbs and ferns from where they are considered "undesirable", they also plant native species of vascular plants where conditions are thought "suitable" for them. The present geographical distributions of such species in Britain may therefore be as much consequences of human prejudice as of their own environmental requirements, and to deduce putative environmental requirements from the geographical distributions of these species is a tautological nonsense. (Really, does anyone still imagine these endeavours are leading inexorably to some new and wonderful law of biogeography?). Bryophytes and other cryptogams, on the other hand, grow where they do largely without human interference, so their geographical distributions indeed offer reliable clues to their environmental proclivities.

3) Another advantage of studying mosses and liverworts is that they provide round- the-year interest for naturalists, unlike many flowering plants, which die back between autumn and spring. Indeed, many annual bryophytes are visible only during the winter months, so the flower-lovers' close season is a time of considerable interest for real botanists.

4) But if neither spotty maps nor the discreet charms of nature's winter greenery are for you, realize that from a global perspective, Britain is a land of bryophytes, not pretty flowers. Mosses and liverworts are much more ecologically important constituents of vegetation in Britain (particularly in the west, where rainfall is high) than on the continent, where fewer species can survive the drier conditions. Britain has two thirds of all European bryophyte species, but only a sixth of the vascular plants. Furthermore, bryophytes constitute much of the biomass of vegetation along the Atlantic seaboard of western Europe, whereas further east bryophytes become less ecologically significant. This makes the West Midlands and Welsh Marches a fascinating region for studying the occurrences and distributions of bryophytes, on the border between drier regions to the east where many species cannot survive (the Breckland of East Anglia, for example, has a notably continental vegetation) and wetter districts to the west where many more species thrive in the mild, moist conditions.

So why aren't there more bryologists?

……….because we do not live in the best of all possible worlds, and several difficulties discourage faint-hearted naturalists:-

1) Many bryophytes are so small that they cannot be identified with the naked eye. Botanists may be lucky even to notice the smallest species in the field, and have to use a lens to identify many more. Even then, a hard core of , "difficult" species remains, whose differences are so slight and minute that they can only be determined microscopically after returning home, so naturalists must possess or have access to a stereoscopic and a compound microscope in order to identify all the bryophytes they find. You need a stereomicroscope in order to dissect leaves from stems, open up gametangia and capsules, etc., and a compound microscope for examining and measuring cells in these structures. Microscopes of poor quality are more of a hindrance than otherwise, while good microscopes cost several hundred pounds, an outlay which deters indigent naturalists from taking up bryology. Moreover, the unavoidable delay between initial discovery in the field and later determination at home may dissuade the impatient and the indolent from taking up bryology.

2) A second difficulty for bryologists is the lack of well illustrated, up-to-date, comprehensive field-guides for identifying British species. This makes it difficult for beginners to get a feel for recognizing plants in the field, leaving bryologists much less well served than lichenologists and mycologists.

3) Bryological beginners also suffer from having few competent field-bryologists they can call upon to help them identify plants which they find. The British Bryological Society has only 600 members, of which perhaps hardly 40 are active in the field. So less than one in a million Britons know their bryophytes, and it's not surprising that few counties have active local groups to which beginners can look for assistance. This deters people from taking up bryology.

Local field-bryology

Yet existence of a local interest group for easing the progress of beginners from initial uncertainty to eventual confidence and competence in the field becomes all the more important because of the lack of a published field-guide and a dearth of competent field-bryologists. Worcestershire is fortunate in having a group which is actively recording in the county, and in addition, the Border Bryologists meet regularly nearer the Welsh border. Their combined activities currently make the West Midlands one of the most vibrant regions in Britain for field-bryology. Local support has never been so good, so now's the time to make the plunge if you're thinking of taking up mosses and liverworts. As further incentive, the British Bryological Society's meeting in spring 2004 will be in Worcestershire, offering local naturalists a week- long opportunity to learn from many of the country's top field-bryologists without having to travel far.

The Border Bryologists' programme of meetings is available from Mark Lawley and is also advertised on the web-sites of the British Bryological Society and Herefordshire Botanical Society (see below). Our meetings are specifically designed to help beginners learn their species, rather than as high-powered recording sessions. In addition to meeting regularly in the field, we hold an annual workshop at Ludlow Museum to familiarise participants with keys, microscopic techniques, and to help them overcome difficulties they have encountered with their gatherings.

Here are some useful contacts:-

British Bryological Society
Hon. Membership Sec:
Mr Mark Pool, 91 Warbro Road, Babbacombe, Torquay, Devon, TQ13PS.
Web-site address: http://www.rbge.org.uk/bbs

Worcestershire bryophytes
BBS recorder for VC 37:
Lorna Fraser, 26 Hinton Avenue, Alvechurch, Birmingham, B48 7L Y

Border Bryologists
Mark Lawley, 12A Castleview Terrace, Ludlow, SY8 2NG. Tel: 01584 876564
e-mail: m.lawley@virgin.net.
Programme of meetings available on-line at http://ralph.cs.cfac.uk/HBS/Border.htm

Herefordshire Botanical Society
web-site address: http//ralph.cs.cf.ac. uk/HBS
Or contact Mark Lawley for details.