SUBTERRANEAN TERMITE (ISOPTERA, RHINOTERMIDAE) PENETRATION INTO SAND TREATED AT VARIOUS THICKNESSES WITH TERMITICIDES

Penetration of the Formosan subterranean termite, Coptotermes formosan us Shiraki, and eastern subterranean termite, Reticulitermes flavipes (Kollar), into sand treated with 1 of the 4 termiticides, Dursban, Bif lex, Dragnet, or Prevail, at treatment thicknesses of 0.15-5 cm was st udied using a laboratory bioassay. Neither termite species penetrated sand containing greater than or equal to 100 ppm termiticide, even whe n the treated barrier was only 0.15 cm thick. Sand treated with 10 ppm Dursban at less than or equal to 0.63 cm was breached by both termite species. Sand treated with 10 ppm Dragnet or Biflex was broken throug h by C. formosanus only when the treatment thickness was 0.15 cm. prev ail at 10 ppm prevented penetration by both termite species. Sand trea ted with 1 ppm Dursban at thickness of 2.5 cm did not prevent penetrat ion by C. formosanus. Biflex was not penetrated by R.flavipes at any c oncentration or thickness. C. formosanus broke through the sand treate d with 1 ppm Biflex when the treatment was less than or equal to 0.63 cm thick. Dursban caused higher mortality than other pyrethroid termit icides.