Cliffs of the Brecon Beacons National Park IPA
Location: Spans 519 square miles of mid-Wales to the north of Merthyr Tydfil.
Grid Reference: SO 009 187
Cliffs of the Brecon Beacons National Park IPA has been recognised as one of 165 Important Plant Areas in the UK.
The key features of this IPA are:
Calcareous rocks with crack & fissure vegetation;
Acid rocks with crack & fissure vegetation;
Beech forests on calcareous soils
Situated between south and mid-Wales, the Brecon Beacons National Park contains some of the most spectacular and distinctive upland formations in southern Britain.
The Park covers an area of 1347 sq km (520 sq miles)m, two thirds of which is comprised of Old Red Sandstone rocks which form four distinct blocks of hills, cut through by major river valleys.
The area's rocky cliffs and carboniferous limestone screes are wonderful places for plants, with over 500 species having been recorded including arctic alpines. They are particularly important for a range of endemic whitebeam trees and hawkweeds. The steep slopes of the Cwm Clydach gorge contain thick native beechwood, rare in Wales.
The Old Red Sandstone cliffs of the Brecon Beacons support variety of arctic-alpine plants, species include the purple, mossy, meadow and rue-leaved saxifrages, procumbent pearlwort, roseroot, green spleenwort and brittle bladder-fern. They are also home to a number of rare hawkweed species and some nationally scarce bryophytes.
The woodland of Cwm Clydach grows on steep slopes alongside a deep river gorge. It is the largest and most representative area of native beechwood in south east Wales. The river has cut deep into the valley forming steep cliffs, and spectacular waterfalls. Clinging precariously to the cliffs are yew and whitebeam trees. Ground plants are relatively sparse in the shade under the beech trees, but there are also areas where the soil is more acidic and in these places, where oak trees tend to be dominant, there is generally a greater diversity of wildflowers.
Because of the humidity caused by the spray from the river, and the dense tree canopy that prevents the moisture from evaporating, the river banks are good places for lower plants such as lichens, mosses, liverworts and ferns, and several interesting species occur there including the lichen Stricta sylvatica and hay-scented buckler-fern.
Other unusual plants to be found here include the bird's-nest orchid, soft-leaved sedge, oak fern and yellow bird's-nest. Near the southern edge of the IPA, Craig y Cilau is one of the largest upland limestone cliffs in Wales, and supports its own characteristic flora, which is unusual in Wales. Here you might find a number of uncommon species such as mountain melick, angular Solomon’s seal, mossy saxifrage or alpine enchanter’s nightshade.