Llanelli Naturalists Newsletter - March 2000 - No 65
Richard Pryce

Leaders: Nigel Stringer, Jim Davies, Ian Morgan, George Hutchinson & Richard Pryce

The party met on a brilliant sunny Saturday afternoon in Heol Hirwaun Oleu, Lower Tumble, before entering the woodland fringing the former opencast site which Carmarthenshire County Council is promoting as a Community Woodland. Richard Pryce reflected on the condition of the area in the early 1970s when numerous colliery tips and general dereliction were present after the closure of the Great Mountain and Blaenhirwaun Collieries. He recalled that the Llanelli Naturalists’ had visited Great Mountain prior to its reclamation by opencasting, in 1977, when about 150 species of plants had been recorded. On that occasion the party had been led by Mrs Vaughan and Mr Tallowin who were able to demonstrate such species as Common Broomrape (Orobanche minor), Wood Horsetail (Equisetum sylvaticum) and Whorled Caraway (Carum verticillatum), all species now vanished.

When opencasting was completed, Pant-y-felin (north of the stream dividing the site) had been restored to forestry, whilst much of Great Mountain site (the southern half of the area) had been left unplanted as the intention had been to use it as a landfill site. Only the extreme southern part of the site had been restored to pasture. Today the forestry plantation is mature but the unplanted area remains with only sparse, naturally recolonised vegetation covering its shaley surface.

The 1999 party were first shown the pond (at SN538125) which had been retained as a feature having had its origin as a settlement lagoon for the Pant-y-felin Opencast Site. Ten species of dragonfles and damselflies have been recorded from here in the past, including the Scarce Blue-tailed Damselfly (Ischnura pumillio), the Emerald Damselfly (Lestes sponsa), the Azure Damselfly (Coenagrion puella) and the Emperor (Anax imperator). It was heavily silted, and was largely choked with a dense stand of Bulrush (Typha latifolia) and some fringing Common Spike-rush (Eleocharis palustris). Hardly any open water remained. There was discussion on the best course of action to take in order to maintain habitats suitable for breeding invertebrates and amphibians whilst also providing a diversity of plant life.

Continuing through the main forest ride there were always some problem species waiting to be discussed - evening primroses (Oenothera spp.), willowherbs (Epilobium spp.), hawkweeds (Hieracium spp.), eyebrights (Euphrasia spp.) and sedges (Carex spp.). Most noteworthy, however, was the enormous population of Common Wintergreen (Pyrola minor) (at SN539128) growing in deep shade under the pines (both Lodgepole Pine (Pinus contorta) and Corsican Pine (P. nigra spp. laricio)), first discovered here in autumn 1997 by Bob and Rannvieg Wallis. It is thought that this species must have been introduced with the young trees when the forest was planted after opencasting ceased; a similar origin is proposed for the numerous small populations of P. minor in Pembrey Forest.

Emerging from the plantation, the party made its way over open, restored grassland of little botanical interest and into the poorly vegetated shaley areas. Seven species of butterflies were recorded here and at the woodland edge, including a single Marbled White, two Graylings and a Wall Brown. Ian Morgan left the main body of the party to take young members to a small tufa flush at SN547127, where an interesting invertebrate find was the Pygmy Soldierfly (Oxycera pygmaea), several of which were caught, the first time he had taken this species. Ian also netted a specimen of the Dark Giant Horsefly (Tabanus sudeticus), actually the largest British species of horsefly, and members had a good opportunity to contrast the 2+cm body length of this impressive beast with the 3mm Pygmy Soldierfly.

The grassland was found to support hundreds of plants of Pennyroyal (Mentha pulegium). Native populations of this species have suffered a serious decline in recent years and it is now protected by its inclusion on schedule 8 of the Wildlife and Countryside Act 1981. Disappointingly, the Tumble population is of the American variety and is likely to have been introduced with the original restoration grassland seed-mix. The other Carmarthenshire population, established on a shingle bar of the Afon Tywi at Llanwrda, is also of the American variety, and is thought to have originated from a garden upstream. Other plants of interest seen by those present included Brown Sedge (Carex disticha), here at one of its three inland Carmarthenshire sites, and Flattened Meadow-grass (Poa compressa), seen here for the first time and only the twelfth vice-county record. Three flowering spikes of Bee Orchid had been seen at the edge of the restored area by Jonathan Price, one of the Council’s Countryside Rangers, in 1997 (c.SN540123), but despite searching for about 30 minutes, no sign was seen of the plants by the 1999 party. Comment was also made on the possibility that Small Blue butterflies may occur as there was a particular abundance of its food plant, Kidney Vetch (Anthyllis vulneraria).