Answer: The tobacco companies probably wouldn't want this to be widely known, but the active ingredient from the tobacco spray that poisoned the pests was nicotine, a broad-spectrum poison that will kill any insect in its path. Although you can make your own tobacco spray, it is no longer recommended for use on food plants. There are other botanical (plant-derived) insecticides available on the market that are much safer when used as directed; pyrethrum and neem are two examples. These are also broad-spectrum, but when you use them properly and only when truly needed, you can have less impact on non-target and beneficial species. Just recently, cottonseed oil has been formulated for use as a suffocating oil spray for use against scale, mealybugs, and other pests.
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