A method and apparatus for detecting internal bio-deterioration in round wood used in various applications (e.g. utility poles, pier pilings, round wood beams, posts and poles in structures, and living trees). The method includes the steps of securing a pulsing transducer adjacent one point on the...http://www.google.com/patents/US5760308?utm_source=gb-gplus-sharePatent US5760308 - Method and apparatus for non-destructively detecting hidden defects caused by bio-deterioration in living trees and round wood materials 
