An apparatus and a method for detecting insect infestation are described. The apparatus includes a cylindrical capacitive sensor including a first semi-cylindrical electrode plate and a second semi-cylindrical electrode plate, wherein the first semi and second semi-cylindrical electrode plates are configured to wrap around the test tree trunk and a processing circuitry, which is configured to measure a capacitance of the test tree trunk when positioned between the first semi-cylindrical electrode plate and the second semi-cylindrical electrode plate and provide a measured capacitance, compare the measured capacitance of the test tree trunk to a reference capacitance of a reference tree trunk, and determine whether an insect infestation is present in the test tree trunk. The cylindrical capacitive sensor can further include another two types of electrode configurations: two pairs of cylindrical electrode strips and two cylindrical electrode rings, wherein the two pairs of cylindrical electrode strips are further configured to positively charge a first pair of cylindrical electrode strips wherein the two the cylindrical electrode strips are oppositely positioned and negatively charge a second pair of cylindrical electrode strips wherein the two cylindrical electrode strips are oppositely positioned, and the two cylindrical electrode rings is further configured to positively charge a first cylindrical electrode ring and negatively charge a second cylindrical electrode ring.