Thermic limitation of AE detection method of old house borer larvae (Hylotrupes bajulus L.) in wooden structures

Abstract

The activity of the old house borer larvae (Hylotrupes bajulus L.) in wood was examined in respect to it’s relationship to ambient temperature. The activity of the larvae was assessed in laboratory experiments based on acoustic emissions (AE) in Scots pine (Pinus sylvestris L.) sapwood at temperatures of −4, 5, 12, 22 and 30°C. 24 or 25 larvae were used at each temperature.The electro-acoustic activity was examined individually for each larva. It was established that below 10°C, the electro-acoustic method of detection should not be used in practice to detect the old house borer larvae. The electro-acoustic method precisely detects and records the presence of the larvae in wood at temperatures ranging from 20 to 30°C, and can be utilised with satisfactory results down to approximately 15°C.