Tree architecture analyses provide pertinent data to practitioners in order to perform an architectural diagnosis. This lecture will guide participants step by step how to read the data provided by researchers and how to perform a basic architectural diagnosis as outlined in Jeanne Millet’s diagnosis guide and Christophe Drénou’s ARCHI method.
In recent years, Christophe Drénou’s ARCHI method: Architectural diagnosis of the vitality of trees, has taken the arboriculture community by storm, regarded as a major contribution to the application of tree architecture in the management of arboreal patrimony. This lecture will guide participants through Drénou’s ARCHI method in a comprehensible accessible way.
Even though the ARCHI method provides specific keys by species, its principles based on the nature of substitute shoots, either orthotropic, plagiotropic or ageotropic, can be extrapolated to many urban trees. The ARCHI method considers two distinct images: A sequential image, corresponding to an ontogenetic diagnosis, considering inherent ontogenetic stages of development, and, a reactive image, corresponding to a physiological diagnosis, considering physiological states induced by the environment, taking into account both mortality and tree reaction.
The ARCHI method enables arborists to understand stress as a pause from a natural state within the inherent sequence of development, leading to physiological states induced by the surrounding environment.
This lecture will describe in detail the 6 different ARCHI types:
Normalcy: Healthy tree presenting normal architecture. Stress: Stressed tree presenting deviations from normalcy. Resilience: Resilient tree returning to normalcy.
Crown retrenchment: Tree presenting a process of construction of a new crown below or nested within the original crown.
Entrenchment: Tree entrenched presenting uppermost crown decline and unaltered lower branches.
Irreversible decline: Declining tree having reached a point of no-return to normalcy.