Coed Afon Pumryd

Also within

Gwynedd County Eryri / Snowdonia National Park

Geology & landscape

Geological Feature: Gorge / Ravine

Landscape processes: Fluvial

Description

Description A biological site considered to be amongst the richest for slime moulds (myxomycetes) in Britain. It is an outstanding site for the group of myxomycetes associated with wet, moss covered rocks and nutrient enriched waters. The group of species is typified by the rare Diderma lucidum, Craterium muscorum, D. ochraceum, Lamproderma columbinum and Lepidoderma tigrinum. These are oceanic species found on shaded north facing rock surfaces with a constant high humidity provided by the Afon Pumryd which cascades down a 20 metre waterfall. The commonest moss substrate is Dicranum scoparium. Amongst the 61 myxomycete species many are rare; Cribraria splendens, Lycogala exiguum and Physarum murinum are the only known Welsh records. The diversity of species is remarkable for such a small area. The woodland in the gorge is dominated by sessile oak Quercus petraea, with beech Fagus sylvatica, ash Fraxinus excelsior and sycamore Acer pseudoplatanus. On parts of the surrounding woodland birch Betula sp. is dominant with large areas of rhododendron Rhododendron ponticum present. The ground flora is varied with grasses predominating such as sweet vernal grass Anthoxanthum odoratum, wavy hair grass Deschampsia flexuosa and sheeps fescue Festuca ovina. Carpets of moss include Isothecium myosuroides, Leucobryum glaucum and species of Polytrichum. Ivy Hedera helix and honeysuckle Lonicera periclymenum are abundant on trees and rocks. Remarks:Within the Snowdonia National Park.

Species mentioned