Fagus sylvatica trees are older than 350 years in Izvoarele Nerei and even 500 years in Uholka-Shyrokyi Luh. Spring leaf budding by the European beech is triggered by a combination of day length and temperature. Bud break each year is from the middle of April to the beginning of May, often with remarkable precision (within a few days). It is more precise in the north of its range than the south, and at than at sea level. The European beech invests significantly in summer and autumn for the following spring. Conditions in summer, particularly good rainfall, determine the number of leaves included
Stigmella hemargyrella Stigmella hemargyrella Stigmella hemargyrella is a moth of the Nepticulidae family. It is found in most of Europe, except Iceland, Norway, Finland, Portugal and most of the Baltic region. The moths (imago) are bivoltine flying from April to May and again from July to August and can be found resting on trunks. The wingspan is 5–6 mm. The egg can be laid on either side of the leaf and the pale yellowish-white larva feed, within a mine on "Fagus sylvatica" and "Fagus sylvatica orientalis". The mine is a sinuous gallery and at the early state is relatively narrow with a