Backstone Bank and Baal Hill Woods one side valley, there is a small population of small-leaved lime, "Tilia cordata", which occurs here close to its northern limit and at an unusually high altitude. On base-rich soils, the woodland typically consists of ash, "Fraxinus excelsior", and wych elm, "Ulmus glabra", over an understorey of hazel, "Corylus avellana", and bird cherry, "Prunus padus", and a rich ground flora that includes lady-fern, "Athyrium filix-femina", male fern, "Dryopteris filix-mas", and hard shield-fern, "Polystichum aculeatum". On more acid soils, sessile oak, "Quercus petraea", and birch, "Betula sp.", are dominant. The under-storey, of hazel, holly, "Ilex aquifolium", rowan, "Sorbus aucuparia", and hawthorn,
Mountain Ash Comprehensive School Mountain Ash Comprehensive School Mountain Ash Comprehensive School (), known as MACS, is a comprehensive school near Cwmpennar near the town of Mountain Ash, Rhondda Cynon Taf, Wales. The school was formerly known as Mountain Ash Grammar School () and is located near the former Dyffryn Colliery. The Welsh Assembly Government placed all secondary schools in Wales into one of five bands according to a number of factors, such as performance across the three core subjects, attendance levels and the number of pupils on free school meals, with one being the best and five being the worst. Mountain Ash Comprehensive