the vegetation is rich and spontaneous : the tall trees are silver fir, mountain maple, scots pine, spruce, black pine, larch, walnut, yew and stone pine ; some floral and shrub species are : rhododendron ( rhododendron hirsutum ), pink heather ( erica carnea ), ranuncolaceae ( clemantis alpina ), heather ( calluna vulgaris ), bilberry ( vaccinium myrtillus ), sorrel ( oxalis acetosella ), gentian minor, carlina, thistle, aconite, jagged thistle and edelweiss. on a sunny day, the perfectly blue sky, fresh air and warm rays make the pure colors of nature brilliant