Biscogniauxia nummularia decline of European beech ("Fagus sylvatica") in Sicily and Calabria (Italy) has been linked to "B. nummularia" and experiments have suggested that this ascomycete plays a primary pathogenic role under certain environmental conditions. It typically causes strip‐cankering and general wood decay. Biscogniauxia nummularia Biscogniauxia nummularia is a plant pathogen in the family Xylariaceae, known as the beech tarcrust. The specific epithet is derived from the Latin "nummus" meaning a coin, referring to the often rounded and coin-like encrustations. The fruit body forms a thick and shiny black crust, on beech ("Fagus") bark and is found at all times of the
Parornix fagivora Parornix fagivora Parornix fagivora is a moth of the Gracillariidae family. It is found from Sweden to the Pyrenees, Italy and Albania and from Great Britain to southern Russia. The wingspan is 11–14 mm. The larvae feed on "Fagus sylvatica", including subspecies "Fagus sylvatica orientalis". They mine the leaves of their host plant. The mine starts as a small lower-surface epidermal corridor with reddish brown frass. Later, it becomes a small rectangular full depth blotch with black frass. The larva deposits only little silk in the mine, that remains practically flat. In the end, the larva leaves the mine and