Abstract: 8 sample trees were selected from an 100-year-old beech wood at seriously polluted Exelberg in Vienna Woods. From the entering area of stemflow and the area between stems contrary to slop direction soil samples were taken. Their pH, contents of vegetable absorbent K, Ca, Mg and Mn, total nitrogen and total carbon as well as contents of Pb and Al were measured. In order to study the effect of soil acidification on beech mycorrhizae at 20 different beech sites of the Vienna Woods humus samples were also taken from the area between stems. According to the following characteristics, colour of the hyPhal mantel, branching form and hyPhae, which grow out from the hyPhal mantel into the soil, the sampled mycorrhizae were divided into 17 individual types. Based upon their anatomical characteristics they were placed into one of two groups: 'healthy' or 'damaged' mycorrhizae. The results from the Vienna Woods show that there is not a strong corelationship between the soil mineral nutrients and the beech mycorrhiza. Effects of Pb and Al which is deposited or dissolved through the stemflow on mycorrhiza are very little. The soil pH is favourable for maintaining mycorrhizae in a vigorous condition (Nr. 1) as long as it is above 4.0.

Key words: Mycorrhiza, Beech(Fagus sylvatica L.), Stemflow, Soil acidification, Acid-alkali buffer reach