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There's more to choosing an insecticide than meets the eye: remember these four things to look for
(1) Derris extract is a botanical insecticide extracted from the roots of derris, with contact and stomach poison action, and is quite effective against aphids and lepidopteran larvae. It is extremely safe for humans, livestock and crops, and is especially suitable for use on fruit, vegetables, tea and mulberry; the usual spray is a 500-800 times dilution of 2.5% derris extract emulsifiable concentrate. (2) Bacillus thuringiensis belongs to Bacu...