Around the hamlet of La Colle, you may be lucky enough to find some star gentian (Gentiana cruciata). This is an herbaceous plant which grows in clumps; it has erect stalks, large, pointed leaves and blue flowers with 4 petals, which are grouped under the upper leaves. This gentian serves as a “nest” for the mountain Alcon blue butterfly (Maculinea rebeli): in this picture, you can distinctly see the eggs laid by the insect.