Abstract
We detected non-destructively the internal defects of the living trees planted in the campus of Shimane University by the lateral impact vibration method, and tried the application of this method to the diagnosis of trees. In this study, we used a product of the lateral impact resonance frequency and the girth as an index of the internal defects. The trees were classified into a few groups by the frequency distribution of the index, and it could give easily recognizable results of the diagnosis. The usefulness of the lateral impact vibration method for preparatory diagnosis of living trees was proved by the index.
