Growth stresses in beech

SummaryMeasurement of the potential deformations contained in standing trees, induced by growth stresses were made using an extensiometric technique which is described. The same extensiometric transducers and methods were also used to evaluate the elastic mechanical properties of green wood necessary to transpose the numeric values of longitudinal microdeformations into mechanical stresses. Measurements were made on 86 different beech trees located in the principal regions of France. The data obtained not only established the feasibility of the method but permitted an objective numeric evaluation of the level of potential deformations found at the base of individual trees. The results could be correlated with the forest environment and also certain morphological and anatomical anomalies within the trees.