Fagus orientalis the buds include flower buds. The flowers are small catkins which appear shortly after the leaves in spring. The seeds are small triangular nuts long and wide at the base; there are two nuts in each cupule, maturing in the autumn 5–6 months after pollination. The cupule differs from that of European Beech in having flattened, slightly leaf-like appendages at the base (slender, soft spines in European Beech). "Fagus orientalis" is closely related to the "Fagus sylvatica" (European Beech), and intergrades with it in the Balkans and northwestern Turkey. These hybrids with European Beech are named "Fagus × taurica". The
Parornix fagivora continues living freely under a folded leaf margin or leaf tip. 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