Sorbus pseudomeinichii Sorbus pseudomeinichii Sorbus pseudomeinichii, known as false rowan and Catacol whitebeam, is a rare tree endemic to the Isle of Arran in south west Scotland. It is believed to have arisen as a hybrid of the native rowan ("Sorbus aucuparia") and the cut-leaved whitebeam ("Sorbus pseudofennica") which is in turn a rowan/Arran whitebeam ("Sorbus arranensis") hybrid. Only two specimens of the Catacol whitebeam are known, making it the rarest tree in Scotland and also the United Kingdom. A third was recorded as a sapling but is believed to have been destroyed by deer. A seedling has also been grown in
Mountain Ash, Rhondda Cynon Taf secondary school is the hospital Ysbyty Cwm Cynon which opened in 2012 replacing the old Mountain Ash General Hospital. Local primary schools include Our Lady's R.C Primary School, Caegarw Primary School (Ysgol Gynradd Caegarw), Glenboi Primary School (Ysgol Gynradd Glen-boi), Darranlas Primary School (Ysgol Gynradd Darren-las), Miskin Primary School (Ysgol Gynradd Meisgyn), Penguelan Primary School (Ysgol Gynradd Pengeulan) and Penrhiwceiber Primary School (Ysgol Gynradd Penrhiwceibr). Mountain Ash has a rugby union team called Mountain Ash RFC. Rugby league club South Wales Scorpions also currently play their home matches in Mountain Ash. Nos Galan (), is an annual running road race,