E1-09 Termite Choice Testing: What is it good for?

Abstract

The prime objective of this investigation was to compare mass loss from termite attack on NHA treated and untreated pine blocks simultaneously in a two-block choice test using Reticulitermes flavipes (Kollar). Southern pine blocks were vacuum treated with aqueous solutions of NHA ranging from 250-10,000 ppm and exposed to one gram of R. flavipes workers in the dual block choice test which included one treated and one untreated block per the modified AWPA laboratory test (E1-09). At the end of four weeks, all test blocks were removed, weighed and the mass losses statistically modeled using SAS version 9.2. Mass loss was consistently greater in the untreated pair-blocks and ranged from 18-35%. Weight loss in the NHA-treated blocks was highest at low concentrations (18%) and decreased to < 1% at 10,000 ppm. termite mortality at the end of four weeks was slight or negligible. we conclude that exposure to untreated pine during exposure to the nha blocks delayed the 100% mortality previously observed in similar no-choice test using similar nha concentrations of nha, either by reducing nha intake below toxic levels or altering gut ph. modest accelerated feeding (stimulation) on the control blocks was observed only in the 2,600 ppm group. overall, nha treatment in pine behaves like a typical repellent wood preservative: as the concentration of preservative increases, feeding and mass loss decreases, however addition of an untreated pine block abrogates the high toxicity of nha to R. flavipes (100%).

Citation

Green, Frederick III; Lebow, Patti; Kartal, S. Nami. 2014. E1-09 Termite Choice Testing: What is it good for?. Proceedings, 108th Annual Meeting of the American Wood Protection Association, April 29 – May 2, 2012. Nashville, TN. 108: 2014; pp. 137-143.