IML Resistograph

The Resistograph is a microdrill designed to record the resistance of wood through a trunk or branch.

Regions of sound wood show high resistance to the forward motion of the drill bit whereas decay weakens the resistance of wood to the drill, and this information is recorded by a stylus trace onto wax paper.

Different trees have different strength characteristics and trees of different levels of health also show a variation in characteristics.

Article written by Steve Cox on November 16, 2009