Rocky Outcrops and Rare Trees – Botany can be exciting and dangerous
Given its size, remoteness and statutory designations it’s hardly surprising that Cwm Elan continuously attracts the attention of naturalists and scientists, making it a novel place to work as we find ourselves assisting in permissions or forays to gather new information perhaps on wood pastures or to find rare species. Both this and last year have proved no exception.
The lone English Whitebeam, Sorbus anglica on Cragg Cnwch, September 2026. Photograph: Dr Tim Rich.
The genus Sorbus includes the whitebeams, service trees and rowans of which there are over 70 species and hybrids in the UK and Ireland. The English whitebeam Sorbus anglica, is a shrub or small tree of inland rock outcrops, sea cliffs, open rocky woods, ungrazed moorland and scrub growing mostly on limestone but occasionally on the more acidic rocks. There are only around 1,000 trees of S. anglica in Britain and Ireland and in 1979 the species was discovered in the Elan Valley by local ecologist Ray Woods, abseiling down cliffs and finding two shrubs on Craig Cnwch and 3 large trees on a rock face at Craig y Foel.
Dr Tim Rich, the UK expert on Whitebeams, risked life and limb to search the cliffs in 2025 and found nothing (apart from an almond tree Prunus dulcis* growing along the Elan Valley Trail) and so asked for our help. Several staff are now adept at flying drones which are used for peat surveys and earlier this month Iona Blockley flew a drone over Craig y Foel. After some initial excitement when the drone picked up large trees with bright red berries in steep gulleys and Tim was able to scramble up the cliff with binoculars close to the location, he discovered that they were just fine specimens of Rowan Sorbus aucuparia.
Thankfully, Tim did that day find a small English whitebeam near the top of Craig Cnwch meaning this species is not yet extinct from Elan Valley. It only had seven berries and Tim urged us to collect some for growing on, in case we lose the rare whitebeam altogether.
Olivia Boston-Smith and I were not looking forward to a steep scramble up and we were grateful to be saved by the news that Sorcha Lewis had collected seed from the Cnwch trees years before and grown them on her farm at Troed Rhiw Draen. Thanks to Sorcha, we were able to pick berries off an easily accessible tree, pot them up and we will aim to plant the trees in suitable locations in the future.
More on fascinating trees next month.
Fiona Gomersall
*The almond could in fact have been an apricot, but what we really need are flowers or fruit to be sure which of these it is. Either tree would be a rather strange find for the Elan Valley – and Rob Andrew, DCWW ranger has assured us that neither were planted! We can only assume that the stone was tossed aside from someone’s snack, 15 or so years ago.
