Anti-termitic efficacy of the resin and rubber in fractionator overheads from a guayule extraction process

Antitermitic properties were evaluated for a mixture of resin and rubber obtained by solvent extraction of guayule. Pine (Pinus strobus L.) sapwood was impregnated with fractionator overheads consisting of resin and low-molecular-weight rubber. The impregnated wood was exposed for 71 months at two sites in the Panama rain forest and for 67 months at a site in the Arizona desert. None of the treated wood sustained any termite damage at either site, whereas untreated baitwood was routinely destroyed. The impregnant mixture acted as a termite antifeedant rather than a repellant. Almost no loss of resin or rubber was sustained by specimens exposed in Arizona, whereas significant losses occurred at both sites in Panama. Environmental factors, including microbiological activity, may have contributed to the loss of both resin and rubber in the rain forest environment. Enough impregnant did remain in the wood to protect it from termite attack throughout the exposure period. (C) 1998 Elsevier Science B.V. All rights reserved.