On July 2, 2019, on the second day of the school, the girls who attended the summer school at the Biotechnical Faculty of the University of Ljubljana spent together with the employees from the Department of Forestry and Renewable Forest Resources.

On a long walk through the entire area of the Tivoli, Rožnik and Šišenski hrib Landscape Park, participants guided by Kristjan Jarni, PhD, learned to identify non-native invasive species including black locust, empress tree, tree of heaven and rudbeckia. Black locust was present almost everywhere and its appearance was strongly related to the light conditions in the stand, as it occurs more abundantly in areas with more light. Participants thus recognized the importance of the amount of light on the presence and vigour of each species and the importance of proper forest management. While empress tree was present mostly individually, tree of heaven was growing in groups, especially in the stands above the Tivoli sport hall and park. Dušan Roženbergar, PhD, presented the research plots established with the aim to demonstrate the possibilities of suppressing and preventing the spread of tree of heaven into natural forests. Studied methods included pulling, breaking and control. Most successful method was pulling.

Authors: doc. dr. Kristjan Jarni, prof. dr. Robert Brus