engleski

Management of Maksimir Urban Forest: Tree Risk Assessment Survey

Urban forests provide numerous benefits which are expressed through ecological and social functions of forests, the most important of which is the recreational function. In order to fulfil those functions it is necessary to have safe and stable forest stands. Maksimir is the oldest and one of the largest urban forest in Zagreb with the total area of 139, 5 ha. On its entire surface there are many tracks used for recreation (walking, walking with dogs, jogging, encounters with people etc.)This work presents the management of Maksimir urban forest through the results of tree risk assessment along main walking tracks. The aim of tree risk assessment is to identify hazardous trees and to suggest arboricultural treatment in order to support healthy trees which will ensure sustainable management of forests. Safety area was defined along walking tracks, and tree risk assessment was done for three main walking tracks, where every tree in the area was examined and only hazardous were registered. The results of tree risk assessment gave grounds for defining tree care measures. The results of research revealed that the main reason for marking a tree as hazardous was a dead tree crown. Most of such trees were in the lower diameter classes, suppressed and overcome by neighbour dominant trees, and should be removed before they become a threat for visitors. Tree risk assessment also includes identification of growth defect symptoms and frequency of mechanical wounds. It was observed that most of the wounds and defects were on the butt end and stem of trees. Protection of those parts of trees is particularly important as most of the trees are in the age of physiological maturity and their site conditions have been altered, which limits them to further dieback. The prescribed tree care intervention for hazardous trees in almost half of the cases was felling, which was mainly associated with dead tree crowns, while a smaller number of trees had mechanical wounds that made them hazardous. Other assigned tree care interventions included pruning of the crown (mainly dead wood pruning overlooking tracks) and further monitoring (with additional inspection). Tree risk assessment revealed the main reason for which trees were rated as hazardous and indicated the need to carry out regular tree care interventions.

safety area; hazard rating; vitality of trees; tree care interventions; urban forest

nije evidentirano