La sostenibilità degli interventi su alberi veterani: un protocollo per la valutazione integrata e la cura

The purpose of this study was to develop and implement a protocol for risk analysis and assessment of veteran trees in public places. One of the main objectives of the management plans of the historical sites is the preservation of the trees "founders". Many of the trees "founder" survivors are subjected to inappropriate management practices, which lowered their life expectancy and greatly reduced their biomechanical safety factor. The protocol developed for the assessment of these trees is based on two types of analysis: a biological assessment of tree health and well-being, and a new method for assessing the biomechanical stability of the tree ( OREBLA - a worksheet digital based tree modeling and evaluation system ). The biological evaluation of tree health is a critical step to evaluate the ability of a veteran tree to react to management practices that lead to the reduction of the biomass. In particular, the metabolic activity of the root system is evaluated by measuring the starch content of the root that has been shown to be related to the response to tree management practices. OREBLA is an integrated tool biomechanical analysis, which includes a modeling of the tree structure based on the protocol EUROCODE for the evaluation of the safety factor of structures exposed to the wind . The evaluation is based on data dendrometric and diagnostic, non-invasive tools for the analysis of the trunk and limbs ( Sonic tomography and electrical ) , and also on an assessment of the risk of tree failure due to fracturing of the plate ( Pulling Test). The protocol was tested in the assessment of veterans 'founders' of the Park trees Revedin Bolasco in Castelfranco Veneto (Italy).