1386 Green shield-moss Buxbaumia viridis
Description and ecological characteristics
Green shield-moss Buxbaumia viridis is a highly-specialised and atypical moss with much-reduced leaves arising from a protonemal mat (i.e. gametophyte generation) and a distinctive capsule (i.e. sporophyte). B. viridis is very specific in its habitat requirements in the UK, being restricted to well-decayed wood, particularly conifer logs, in damp, sheltered places in woodland. However, in mainland Europe it occurs on rotten wood of various sorts and has been recorded growing on humus-rich soil and on weathered, acidic rocks.
European status and distribution
Buxbaumia viridis is widespread in Europe, but is apparently declining, rare and threatened in most countries, and is listed as Vulnerable. This may be because of destruction of, and commercial forestry practices in, semi-natural coniferous woodland.
UK status and distribution
In the UK, Buxbaumia viridis has only ever been found in a small number of sites in northern and eastern Scotland, with a very small number of plants at each site. It is listed as Endangered in Britain. It is currently known from four sites: Rothiemurchus Forest and Abernethy Forest, both in the Cairngorms, Moniack Glen near Inverness and Kindrogan in east Perthshire.
Site selection rationale
Three of the known sites are included within two SACs selected for this species in the UK. The two SACs are thought to hold a large proportion of the total UK population.
Highlands and Islands, North Eastern Scotland
Green shield-moss Buxbaumia viridisB. viridis at Rothiemurchus had sporophytes, four in total and much fewer than in 2002. However, three new stands, close together, were found at Abernethy with a total of eight sporophytes. Areas of woodland with apparently suitable habitat were found to be very patchy, but a number of areas with good potential habitat were identified. It is thought possible that further survey may result in more new records for the species. Although sporophyte production is small, it is broadly comparable with that at the site at Moniack Gorge, Highland, and greater than that at Kindrogan, Perthshire. Given the extant records and the potential for discovery of further stands, the Cairngorms area is probably the most important locus for the species in the UK.
Highlands and Islands
Moniack Gorge in north-east Scotland is a steep wooded ravine with predominantly base-rich soils. This is one of only three UK sites where green shield-moss Buxbaumia viridis has been recorded in recent years. Twenty-three sporophytes were recorded on four logs at three places in 1999, which represents a large proportion of the known UK population. Habitat conditions appear suitable, as there is evidence that the species has been present at the site for many years.
Many designated sites are on private land: the listing of a site in these pages does not imply any right of public access.