Large and Old Trees (LOTs) in urban environments are of crucial importance, since they have a very high carbon storage capacity, while their structural complexity favors a richer biodiversity than recent or newly planted trees. In general, these trees offer a wide range of ecosystem services and need to be managed in a planned way. Consequently, the location of GVAs and their characterization (size, type, cavities, branching structure) are parameters that need to be known in order to plan management and preservation operations. To obtain these data, LiDAR technology is an effective alternative thanks to its ability to acquire highly accurate data on vegetation structure in 3 dimensions, at different spatial and time scales. In this project, we aim to detect, map and characterize GVA in urban environments. To achieve this, we will exploit terrestrial LiDAR data acquired on tripods or by mobile scanning. This research will be carried out in collaboration with Alain Paquette and his team (PaqLab, Université du Québec à Montréal).