Mercurialis perennis
The shallow soils that have developed on ledges and crevices in the limestone and on the scree slopes support a vegetation in which ferns such as maidenhair spleenwort, "Asplenium trichomanes", green spleenwort, "A. viride", and brittle bladder fern, "Cystopteris fragilis", are prominent. Woodland plants such as wood sorrel, "Oxalis acetosella", wood millet, "Milium effusum", and dog's mercury, "Mercurialis perennis", have established themselves in the shadier crevices, while rue-leaved saxifrage, "Saxifraga tridactylites", shining cranesbill "Geranium lucidum", and common whitlow grass, "Erophila verna", occur in the most exposed situations. On the most inaccessible valley slopes, there is open woodland in which yew, "Taxus baccata", is abundant.