Snake venom, arsenic, poison ivy—they're all natural, but that doesn't make them safe. By the same token, there are many natural toxins used in organic garden products that are potentially harmful. If misused, natural poisons, such as pyrethrin (an insecticide extracted from chrysanthemum flowers), are hazardous to people, pets, and the beneficial inhabitants of our gardens, such as frogs and bees. If you must use a pesticide, base your selection on how dangerous the active ingredients are, and how effective. Safer choices include products that contain Bacillus thuringiensis, aka Bt, and insecticidal soap.