The use of ultrasonic measurements to distinguish between borer-damage
d and nonborer-damaged fruit trees is presented. When a fruit tree is
damaged by borer infestation, the properties of the boundary between t
he bark and the trunk of the cherry tree change, and if the borer dama
ge is extensive, large spatial cavities occur. The damaged areas conta
in a greater percentage of air space, feces, Ean,ae, or other low dens
ity matter when compared with samples from nonborer-damaged areas. The
theoretical basis for ultrasonic detection of borer damage is describ
ed. A microcomputer based detection system is described and data obtai
ned from damaged and nonborer-damaged frees is presented.