Abstract:The osier weevil is a wide destroyer of poplar in some parts of the world.This pest is mainly controlled by using conventional pesticides atpresent. These pesticides not only pollute the enviroment, but also cost a lots.From 1987 to 1990, the oil solution and flowable oil colloid ofbenzoylphenol uera No. 3, which are safe, high effective and low cost, weremanufactured, and the spot treatment and hole block methods were used in thecontrolling of the osier weevil in the larval and the adult stages. Themechanisms of the effect of benzoylphenol urea No. 3 on the larva and the adult of this pest is discussed. Experimental results showed that comparing with the larvae of untreated group, more than 15 per cent chitins in theendocuticle of treated larvae was reduced. The spraying of 15%-25% of flowable oil colloid of benzoylphenol urea No. 3 made the ovary and the testis can not develop, and the number of eggs laid by the treated hatching rate of those eggs became zero. The oil solution and flowable oil colloid ofnenzoyphenol urea No. 3 can be effectively used in the control both of the larva and the adult of the oser weevil. The use of these insecticides opens a new way for the control of the osier weevil.