Efficacy and Persistence of Chorpyrifos, Chorpyrifos-methyl, and Lindane for Preventive and Remedial Control of the Southern Pine Beetle12

Field tests with selected insecticides for preventive and remedial control of Dendroctonus frontalis Zimmermann were conducted in 1975 and 1976. In preventive control tests, 1 and 2% chlorpyrifos (Dursban® formulation) 1 and 2% chlorpyrifos-methyl (Reldan® formulation) compared favorably with 0.5% lindane at 2 and 4 months posttreatment. At later intervals, lindane was more effective than either chlorpyrifos or chlorpyrifos-methyl. The persistence of lindane, chlorpyrifos, and chlorpyrifos-methyl was compared to efficacy data from the preventive control studies. Results indicate that lindane dissipated from bark more rapidly than either chlorpyrifos or chlorpyrifos-methyl. As a remedial control agent, 1 and 2% chlorpyrifos compared favorably with 0.5% lindane. Selected extender-sticker adjuvants were only slightly effective in improving the persistence of chlorpyrifos and lindane on bark.