Feasibility of ultrasonic tomography for nondestructive testing of decay on living trees

Both laboratory and field ultrasonic measurement were carried out to assess the feasibility of ultrasonic tomography for non invasive testing on living trees. Trees with internal decay were investigated and later cut down. the laboratory measurements performed on wood disk and specimens, led to quantitative assessments of the reliability of the tomographic results. Statistical analysis of data allowed considerations to be made on the main aspects connected to the homographic imaging, such as uncertain spatial resolution and anisotropy. The obtained results show that the homographic imagine of the ultrasonic velocity distribution is in good agreement with the distribution of the wood decaying the investigated section and the proposed methodology therefore seems to be as improvement on currently used surveying methods.