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57 Ways To Protect Your Home Environment (and Yourself)
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11. Consider Botanical Insecticides and Insecticidal Soaps

Botanical insecticides

Botanical insecticides, sometimes referred to as “botanicals,” are naturally occurring insecticides derived from plants. Insecticidal soaps are soaps that have been formulated specifically for their ability to control insects.

Botanical insecticides and insecticidal soaps degrade readily in the sunlight, air, and moisture, breaking down into less toxic or nontoxic compounds and posing less risk to nontarget organisms. But this requires you to precisely time your application. You may also need to make more frequent applications if you observe additional damage.

botanical label

Most botanicals do not damage plants. Plus, most botanicals and insecticidal soaps are low to moderate in toxicity to mammals, but there are exceptions. For example, both inhalation and skin exposure to nicotine preparations can cause death. Also, rotenone is similar in toxicity to the common synthetic insecticides carbaryl and diazinon.
Pictured are Japanese beetles.

Botanicals and soaps may not kill an insect for hours or days, but they act very quickly to stop its feeding. It must be noted that data on effectiveness and long-term toxicity are unavailable for certain botanicals.
spraying a house plant

Botanicals tend to be more expensive than synthetic pesticides, and some are not as widely available. Also, the potency of some botanicals may differ from one source or batch to the next.
Botanical Insecticides

Common botanical insecticides include pyrethrum and pyrethrins—a dust or extract derived from the pyrethrum daisy. These products are registered for use on animals to control fleas, flies, and mosquitoes. They are also used as indoor household sprays, aerosols, and “bombs.” Pyrethrins are sometimes combined with rotenone and ryania or copper for general use in gardens.
Botanical Insecticides

Rotenone is derived from the roots of tropical legumes. It is particularly effective against leaf-feeding beetles and certain caterpillar pests. It is also very toxic to fish. Rotenone persists for a few days on treated foliage—longer than most other botanical insecticides.
Botanical Insecticides

Sabadilla is effective against certain “true bug” insects such as harlequin bugs and squash bugs, which are difficult to control with most other insecticides. Sabadilla is highly toxic to honey bees, so avoid spraying it when bees are present.
Botanical Insecticides

Ryania may be used on citrus, corn, walnuts, apples, and pears for the control of such pests as citrus thrips, European corn borer, and codling moth. Nicotine is used in greenhouses and gardens to control soft-bodied sucking pests such as aphids, thrips, and mites. Because they can be toxic to humans, nicotine teas are not recommended as a way to control garden or household pests.
Botanical Insecticides

Limonene and linalool are especially common in flea dips and pet shampoos. And the compound azadirachtin, derived from the neem tree, is sold under various names, including Align, Azatin, Neemix, and Bio-Neem. It may be used on several food crops and ornamental plants to control white flies, thrips, mealybugs, and other pests.
Botanical Insecticides

Insecticidal soaps are used to control soft-bodied pests such as aphids, thrips, scales, whiteflies, leafhopper nymphs, and mites. Soaps are effective only against those insects that come into direct contact with sprays before they dry. Soaps are particularly useful for controlling insects that damage ornamental plants and houseplants, though they can be toxic to some plant species.
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