Leaders Kath & Richard Pryce
On a beautiful spring day a mixed group of Llanelli Naturalists and Wildlife Trust members met at Pembrey Harbour to look at the dune system eastwards to Burry Port Harbour. Richard first showed us typical members of the established dune community such as Goat’s beard Tragopogon pratensis, Burnet‐rose Rosa pimpinellifolia (one plant obligingly early in flower), Dewberry Rubus caesius, Sand Sedge Carex arenaria and Bulbous Buttercup Ranunculus bulbosus. We also saw several thickets of Sea buckthorn Hippophae rhamnoides, not native to this part of Britain and a scourge of the dunes in this area as it is a vigorous coloniser which stifles most other ground cover.
Further on were more characteristic dune plants like yellow‐flowered Lady’s Bedstraw Galium verum, Hairy Rock‐cress Arabis hirsuta, Red Fescue Festuca rubra and the abundant Sand‐hill Screw‐moss Syntrichia ruralis ssp. ruraliformis. The prolonged dry weather had brought forward the flowering time of several species such that they were now senescent, desiccated and hard to see. These included Common Whitlowgrass Erophila verna, while the Sand‐hill Screw‐moss was brown and apparently lifeless. Harsh conditions and lack of available water for much of the year favour such mosses which return to their photosynthetic green state on wetting, whilst winter germinating early annuals can produce seed before being killed by summer drought.
Some of the group saw a very obliging Mother Shipton moth Callistege mi, which even when disturbed, alighted only a short distance away and allowed us a good view. This is named after a 16th century Yorkshire witch and soothsayer as the wing pattern is said to resemble her profile with a hooked nose and prominent chin and eye.
Moving on to flatter ground we saw Bloody Crane’s bill Geranium sanguineum (escaped from a nearby caravaner’s garden) and Perforate St.John’s‐wort Hypericum perforatum whilst in short turf subject to more regular traffic and heavy rabbit‐grazing there was Wild Mignonette Reseda lutea, Common Storksbill Erodium cicutarium, Buck’s‐horn Plantain Plantago coronopus, Sand Cat’s‐tail Phleum arenarium and Dove’s‐foot Cranesbill Geranium molle. We looked through the perimeter fence of the pickle factory (a former tinplate works) where vegetation was more rank and includes extensive and impressive stands of Wild Mignonette and Great Mullein Verbascum thapsus both of which obviously enjoy the sandy soil with readily available calcium from the discarded shells of cockles which had ended up being pickled.
Nearby on slaggy, gravelly ground we looked for Subterranean Clover Trifolium subterraneum which had been noted there by a BSBI group some years earlier and is notable for flower heads which turn down and thrust seeds into the ground. The prolonged dry weather had desiccated these early species and we failed to find any small annual clovers. We did, however, see Lesser Trefoil Trifolium dubium, along with Common Mallow Malva sylvestris and Round leaved Crane’s‐bill Geranium rotundifolium.
We noted a patch of Salad Burnet Sanguisorba minor, just west of the Yacht Club, a plant which enjoys short turf with readily available calcium and caused by the leaching of this element from shell fragments which make up a high proportion of the sand grains. South of the Yacht Club, by the promenade skirting the western side of Burry Port Harbour, Richard pointed out Dwarf Mallow Malva neglecta, rare in Carmarthenshire but just surviving despite regular strimming by Millennium Coastal Park staff, mismanagement which is contrary to the agreed management plan. We also saw Sea bindweed Calystegia soldanella with its attractive pink and white striped flowers and then on a barish dune‐tump several plants of Sand Catchfly Silene conica, a few flowers still open, although most open early and wither by mid‐day. This is an annual, declining nationally, which only sets seed well in hot summers and, from year to year, plants tend to be seen irregularly in various places over the dunes.
Some of the group returned via the beach where Richard demonstrated the diversity of source rock to be found among the shingle. There were some fairly local rocks but also porphyry, granites and other igneous rocks which had been moved south‐east by glacial action from Pembrokeshire or further north. Some was local slag from past iron and copper smelting but much had been derived from dumping of ships’ ballast and included flint originating from the Chalk of southern and eastern England or northern France. Because prevailing winds and tides result in long‐shore drift moving the material gradually in an eastward direction, it suggests that this ballast may be from a time when Pembrey Harbour was in use, though due to rapid silting and lack of adequate scouring currents, its period of significant commercial use was brief and was soon replaced by Burry Port Harbour.
The party eventually reached its starting point at Pembrey Harbour, which was dry and now silted and colonised by saltmarsh though still inundated during high tides. The former scouring pond to the north of the harbour was used as a land‐fill site in the 1960s and has since been grassed over. Plants seen in the harbour included Sea Beet Beta vulgaris ssp. maritima, Common Sea Lavender Limonium vulgare, Sea Purslane Atriplex portulacoides, Lesser Sea‐spurrey Spergularia maritima and glasswort Salicornia sp., named because it was burnt to provide a source of Sodium carbonate for glassmaking. It was a reminder of the long heritage of industry and the shipping of minerals in the area, which has profoundly altered the landscape and contributed to this 10km square SN40 having the greatest botanical diversity in Wales (also as a result of local botanists’ diligent recording).
Many thanks to Richard and Kath for a most informative and enjoyable afternoon.