Dust powder formulations were prepared for the following plant parts directly as plant powders and for their extracts with ethanol, using talc and mosaic as diluents for preparing dusts. The plant parts were : leaves of shih (Artemisia cina), gum of sorrel (Rumex vesicarius) and seeds of kalakh (Ferula communis). The locally prepared dusts were eval­uated against adults, eggs and the offspring of C.maculatus that infested cowpea seeds. Results obtained proved that dusts of plant extracts were faster and much more efficient than dusts of normal plant powders either in their initial or residual effect after 3 months of treatment. Dust of sorrel ext./mosaic was the most efficient dust against adults, eggs and the offspring of C.maculatus followed by sorrel ext./talc, kalakh ext./talc and shih ext./talc.