SYSTEMIC ACTION OF NEEM SEED EXTRACT ON MOUNTAIN PINE-BEETLE (COLEOPTERA, SCOLYTIDAE) IN LODGEPOLE PINE

A botanical insecticide derived from seeds of the neem tree, Azadirachta indica A. Juss, was tested for the ''bait and kill'' strategy for control of outbreaks of the mountain pine beetle, Dendroctonus ponderosae Hopkins. Application of neem into frills at the base of beetle-attacked lodgepole pine, Pinus contorta Douglas var. latifolia Engelmann, trees reduced numbers of mountain pine beetle larvae per unit area of bark, decreased densities of larvae per unit length of adult gallery, and increased larval mortality when applied at doses >0.25 g (AI) (azadirachtin) per tree. Suggestions for improving the efficacy of neem treatments are discussed.