Insects

The LIFESPAN protection system also contains an insecticide, permethrin, which is effective against insects, including termites. The permethrin retention (0.02%m/m) used in LIFESPAN is approved in both Australia (AS1604) and New Zealand (NZS3640) and has been extensively used for out of ground contact applications.

A recent trial by CSIRO, Australia (Susceptibility of Envelope-Treated Softwood to Subterranean Termite Damage, by James W. Creffield. Forest Products Journal, December 2004) examined the performance of permethrin, as both an envelope and fully impregnated, against termites. Samples were exposed for 12 months at Gunn Point, Darwin, and Northern Territory, Australia where a species of termite, Coptotermes acinaciformis, is prevalent. All specimens showed evidence of contact with termites, indicating activity. The full penetration treatments with 0.02%m/m permethrin had a mean rating of 1.2 (radiata pine) with a range of 1-2, and 1.0 (slash pine). Untreated samples had a mean rating of 6.3 with a range of 5-7 (1 being sound; 7 being destroyed [75 to 100% mass loss]).

Further samples were exposed at Beerburrum, Queensland where both C. acinaciformis and Schedorhinotermes spp. occur. Samples were examined after seven months. Samples that were fully treated with 0.02%m/m permethrin had no weight loss due to termite attack, whereas untreated controls had a weight loss of 16.2 to 262.5g.

The successful control of termite attack by permethrin in Australia, involving a number of different termite species, provides an assurance that LIFESPAN products will also be protected from attack by the Formosan termite, C. formosanus.