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 randaiensis change of leaves to red and rubine fruits in October. The fruits are with juicy texture and sweetness, tasting delicious. Sorbus randaiensis Sorbus randaiensis is a deciduous tree of family Rosaceae. It is an endemic species in Taiwan and can be found in the mountain areas of middle Taiwan, with altitude 1,800m to 3,200m, mostly spotted in the forest of Xueshan, Hehuan Mountain, , and Nenggao Mountain. It is a tree 3–8 m tall with white flowers and reddish fruit. Koidz., The Journal of the College of Science, Imperial University of Tokyo, Japan 34(2): 52. 1913. (J. Coll. Sci. Univ.