Field experiments conducted on black pepper during summer, 2007 and 2008 to find out the efficacy of certain leaf extracts on mussel scale (Lepidosaphes piperis Gr.) reveal that all the leaf extracts were able to reduce thescale population significantly over control. Cleome gynandra (Spider flower) leaf extract 5% (9.8 scales / cm2 / leaf ), followed by Azadirachta indica (Neem) leaf extract 5% (10.8 scales/ cm2 / leaf) were very effective and proved to be the best with 28.09% and 21.13% reduction of scales population respectively over control (13.6 scales / cm2 / leaf). Similarly, Azeratum conyzoides (Goat weed), Annona squamosa (Custard apple), Parthenium hysterophorus (Congress weed) and Lantana camara (Yellow sage) respectively with 11.6, 11.8 11.9 and 12.2 scales per cm2 per leaf have recorded 14.20 13.31, 12.19 and 9.92% reduction of population over control respectively. Results indicated that plant extracts could be used as potential botanical pesticides for organic farming.