| Scheffrahn, R. H., W. P.
Robbins, P. Busey, N. Su, and R. K. Mueller. 1993. Evaluation
of a novel, hand-held, acoustic emissions detector to monitor
termites (Isoptera:Kalotermitidae, Rhinotermitidae) in wood.
J. Econ. Entomol. 86:1720-1729.
Abstract
A hand-held, battery-powdered acoustic emissions (AE) detector
designed to locate and monitor wood-feeding insects was evaluated
for its ability to detect termites in wood. It was possible
to detect 20 Coptotermes formosanus Shiraki, Incisitermes
snyderi (Light), and Neotermes jouteli (Banks)
pseudergates in small wooden blocks 100% of the time during
an experimental 5-min interval. If undisturbed, 20 Reticulitermes
flavipes (Kollar) pseudergates could be detected at a
98% frequency. AE production was governed largely by termite
species and density. In detection tests along longitudinally
oriented wood grain, termites could be detected up to 80 cm
from the AE sensor, although detection at progressively shorter
distances from termites was increasingly more likely. Detection
of termites in wood in a tangential orientation (against grain)
was unlikely beyond 8 cm. Although counts were high (up to
299 per min), there was a poor relationship between I.
snyderi numbers and AE event counts in naturally infested
logs. The only termite behavior observed to elicit detection
by the AE units was wood feeding. Most ambient noises were
not registered by the detector. It was concluded that this
device offers a reliable method for localized, nondestructive
detection of termites in wood.
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