Trees in a city lift by the fulfilment of a huge number of different functions the quality of life of the inhabitants. Nevertheless, the varied activities of the people mostly stand in the way of the biological interests of the trees what reduces on the one hand their vitality and, on the other hand, their life expectancy and hinders them, in the end, in the comprehensive fulfilment of the functions intended to them. This diploma thesis deals with the analysis of 105 jung trees in the city of Zell am See to be able to derive improvement possibilities for the planning plantation and care. In the first part of the work the living conditions for trees in the city are looked at by means of literature research and the state of the technology for the successful contact with city trees is demonstrated. In the second part via statal ascertainment and soil analysis the location terms, the general situation and the nursing state of the chosen stock of trees is aligned with recommendations from the technical literature. A comparison of vitality and soil sampling should bring knowledge of the influential factors. Furthermore a comparative analysis of a street with trees of the same age and the same kind, however, with different location relations and nursing relations is carried out to recognise important connections. Finally comparable results of a similar thesis on this subject, which was carried out in Krems an der Donau, will be confronted with results from this thesis. The results show that, above all, especially in strongly frequented traffic routes enough decorated stand space is not intended for the trees. From the soil analyses it arises that the grain size distributions of the examined substrates mostly does not correspond to the recommendations. There is improvement need also in the production and care of the tree protection facilities, the care of the tree grate surfaces and by the realisation of cut measures.