Early identification of root damage in growing wood esp. trees caused by gnawing vermin

摘要

The root damage identification involves transmissions of an electrical output signal from the body of a sound pick-up using pref. an acceleration pick-up (11). Each trunk (101) of the fruit trees (10) has an acceleration pick-up fixed to it. An evaluation station (12) is provided, which is connected to the signal outputs of the tree trunks. the gnawing noises are detected in the time signal of the pick-up output signal. The gnawing noises are detected in the power spectrum of the pick-up output signal. The fixing of the pick-up at the trunk results near to the ground, e.g. at a distance of about 20 cm above the ground surface. Due to the activity of the gnawing vermin leads to cyclic recurring pulse signals at the outputs of the pick-ups.