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,
Sorbus aucuparia tannin, and vitamin C. The seeds contain glycoside. "Sorbus aucuparia" has a chromosome number of 2"n"=34. "Sorbus aucuparia" is found in five subspecies: It can be found in almost all of Europe and the Caucasus up to Northern Russia and Siberia, but it is not native to Southern Spain, Southern Greece, Sardinia, the Balearic Islands, the Azores, and the Faroe Islands. The species was introduced as an ornamental species in North America. It is widespread from plains to mountains up to the tree line where it grows as the only deciduous tree species among krummholz. In the Alps it grows